fix(launcher): remove hard-coded Python 3.13 path

BUILD.md

@@ -5,16 +5,25 @@ OpenSpan ships as source, but it also packages into ONE standalone
 
 ## Build
 
+Use whatever local Python 3.x with PyInstaller you have — it is never
+hardcoded to a version or path. Two equivalent forms:
+
 ```
-C:\Python313\python.exe D:\OpenSpan\build_exe.py
+:: from the repo folder: any local 3.x works, e.g.
+py -3 build_exe.py
+:: or
+python build_exe.py
 ```
 
-Needs PyInstaller (`pip install --user pyinstaller`; already present here).
-Produces `D:\OpenSpan\OpenSpan.exe` (~64 MB). It runs **in place** — the app
-anchors every data file on the exe's own folder, and `D:\OpenSpan\` already
-holds them, so there's nothing to assemble. `OpenSpan.bat` and the Start-Menu
-shortcut auto-prefer the exe when it exists and fall back to the Python
-entry point otherwise.
+Needs PyInstaller in the active interpreter
+(`py -3 -m pip install --user pyinstaller`; already present on the author
+machine). Produces `D:\OpenSpan\OpenSpan.exe` (~64 MB). It runs **in place**
+— the app anchors every data file on the exe's own folder, and `D:\OpenSpan\`
+already holds them, so there's nothing to assemble. `OpenSpan.bat` and the
+Start-Menu shortcut auto-prefer the exe when it exists and fall back to the
+Python entry point otherwise (the .bat resolves the interpreter
+dynamically: pyw.exe → pythonw.exe → python.exe → registered installs,
+validating tkinter per candidate — no hardcoded paths).
 
 ## How the one file does three processes
 
@@ -49,5 +58,8 @@ is rebuilt on demand, not stored in the repo.
 
 Built `--noconsole` (GUI, no console flash) with PyInstaller's `runw`
 bootloader, and unsigned-but-unflagged, so it launches unelevated — dodging
-the same shell-reputation gate that made the `openspanw.exe` interpreter copy
-necessary for the raw `.py` path.
+the same shell-reputation gate that a RUNASADMIN-flagged `pythonw.exe` copy
+would trip (the raw `.py` path is covered by `OpenSpan.bat`'s dynamic
+interpreter resolution: pyw.exe → pythonw.exe → python.exe → registered
+installs, each validated with `import tkinter`; no renamed `openspanw.exe`
+needed anymore).

OpenSpan.bat

@@ -1,8 +1,102 @@
 @echo off
-rem Prefer the packaged single-file exe if it's been built; otherwise fall
-rem back to the Python entry point via the unflagged interpreter copy.
-if exist "%~dp0OpenSpan.exe" (
-  start "" "%~dp0OpenSpan.exe"
+rem ---------------------------------------------------------------------------
+rem OpenSpan launcher
+rem
+rem  1. A packaged OpenSpan.exe next to this file wins, always.
+rem  2. Otherwise pick the BEST locally available Python GUI interpreter --
+rem     NOTHING hardcoded: no install paths, no usernames, no renamed-copy
+rem     tricks. Candidate order:
+rem        a) pyw.exe         (Windows Python Launcher, console-less)
+rem        b) pythonw.exe     (on PATH, console-less)
+rem        c) python.exe      (on PATH, console fallback)
+rem        d) registered PythonCore installs (newest 3.x, pythonw preferred)
+rem     Every candidate is validated with "import tkinter"; a broken
+rem     candidate is skipped, never trusted.
+rem  3. Clear error surfacing: "no Python found" vs "Python found but
+rem     tkinter missing" -- never a raw "missing interpreter" error.
+rem ---------------------------------------------------------------------------
+setlocal EnableExtensions EnableDelayedExpansion
+set "ROOT=%~dp0"
+
+rem -- packaged exe wins ------------------------------------------------------
+if exist "%ROOT%OpenSpan.exe" (
+    start "" "%ROOT%OpenSpan.exe"
+    exit /b 0
+)
+
+set "FOUND_WITHOUT_TK="
+
+rem -- 1) Windows Python Launcher (pyw.exe = console-less variant) ------------
+for /f "delims=" %%W in ('where pyw.exe 2^>nul') do (
+    if not defined PYW_CMD set "PYW_CMD=%%W"
+)
+if defined PYW_CMD (
+    "%PYW_CMD%" -3 -c "import tkinter" >nul 2>&1
+    if not errorlevel 1 (
+        start "" "%PYW_CMD%" -3 "%ROOT%win\openspan.py"
+        exit /b 0
+    )
+    set "FOUND_WITHOUT_TK=%PYW_CMD% (-3, tkinter import failed)"
+)
+
+rem -- 2) pythonw.exe on PATH (console-less GUI interpreter) ------------------
+set "PYWW_OK="
+for /f "delims=" %%W in ('where pythonw.exe 2^>nul') do (
+    if not defined PYWW_OK (
+        "%%W" -c "import tkinter" >nul 2>&1
+        if not errorlevel 1 (
+            set "PYWW_OK=%%W"
+        ) else (
+            if not defined FOUND_WITHOUT_TK set "FOUND_WITHOUT_TK=%%W"
+        )
+    )
+)
+if defined PYWW_OK (
+    start "" "%PYWW_OK%" "%ROOT%win\openspan.py"
+    exit /b 0
+)
+
+rem -- 3) python.exe on PATH (console fallback; skip the Store stub) ----------
+set "PYEXE_OK="
+for /f "delims=" %%W in ('where python.exe 2^>nul') do (
+    if not defined PYEXE_OK (
+        echo %%W | findstr /i "WindowsApps" >nul 2>&1
+        if errorlevel 1 (
+            "%%W" -c "import tkinter" >nul 2>&1
+            if not errorlevel 1 (
+                set "PYEXE_OK=%%W"
+            ) else (
+                if not defined FOUND_WITHOUT_TK set "FOUND_WITHOUT_TK=%%W"
+            )
+        )
+    )
+)
+if defined PYEXE_OK (
+    start "" "%PYEXE_OK%" "%ROOT%win\openspan.py"
+    exit /b 0
+)
+
+rem -- 4) registered PythonCore installs (newest 3.x; pythonw.exe, tkinter-ok) -
+set "REGPW="
+for /f "usebackq delims=" %%P in (`powershell -NoProfile -ExecutionPolicy Bypass -Command "$vs=@(); foreach ($root in 'HKCU:\SOFTWARE\Python\PythonCore','HKLM:\SOFTWARE\Python\PythonCore') { Get-ChildItem $root -ErrorAction SilentlyContinue | ForEach-Object { $ip=(Get-ItemProperty ($_.PSPath + '\InstallPath') -ErrorAction SilentlyContinue).'(default)'; if ($ip -and (Test-Path ($ip + 'pythonw.exe'))) { $parts=$_.PSChildName -split '\.'; $vs += [pscustomobject]@{ V=([int]$parts[0])*100+[int]$parts[1]; P=$ip } } } }; $best=$vs | Sort-Object V -Descending | Select-Object -First 1; if ($best) { $best.P }"`) do (
+    if not defined REGPW set "REGPW=%%P"
+)
+if defined REGPW (
+    if exist "%REGPW%pythonw.exe" (
+        "%REGPW%pythonw.exe" -c "import tkinter" >nul 2>&1
+        if not errorlevel 1 (
+            start "" "%REGPW%pythonw.exe" "%ROOT%win\openspan.py"
+            exit /b 0
+        )
+        set "FOUND_WITHOUT_TK=%REGPW%pythonw.exe"
+    )
+)
+
+rem -- nothing usable: say so, clearly ----------------------------------------
+if defined FOUND_WITHOUT_TK (
+    set "ERRMSG=Python was found (%FOUND_WITHOUT_TK%) but it cannot import tkinter. Use a standard python.org 3.x (tkinter included), no PATH changes needed."
 ) else (
-  start "" "C:\Python313\openspanw.exe" "%~dp0win\openspan.py"
+    set "ERRMSG=No usable Python interpreter was found. Install a standard python.org 3.x from https://www.python.org/downloads/ and run this file again -- no PATH changes needed."
 )
+powershell -NoProfile -ExecutionPolicy Bypass -Command "Add-Type -AssemblyName PresentationFramework; [System.Windows.MessageBox]::Show('%ERRMSG%', 'OpenSpan - Python not usable', [System.Windows.MessageBoxButton]::OK, [System.Windows.MessageBoxImage]::Error)"
+exit /b 1

TECHNICAL_NOTES.md

@@ -166,8 +166,11 @@ Windows input portal (openspan_portal.py, captures at the screen edge)
 - **On-demand only.** Launches from a Start Menu shortcut *or*
   `D:\OpenSpan\OpenSpan.bat`. The launcher prefers the packaged
   **`OpenSpan.exe`** (single file, built via `build_exe.py` — see BUILD.md)
-  when present, and falls back to **`C:\Python313\openspanw.exe
-  win\openspan.py`** otherwise.
+  when present, and otherwise resolves a real local Python interpreter
+  **dynamically** (pyw.exe launcher → PATH pythonw.exe → PATH python.exe →
+  newest registered PythonCore install; every candidate is validated with
+  `import tkinter`; broken candidates are skipped and clear errors are
+  surfaced instead of a stale hardcoded path).
 - **Single-file packaging (2026-07-12).** `build_exe.py` → PyInstaller →
   one ~64 MB `OpenSpan.exe` that runs in place (data files anchor on
   `sys.executable`'s folder, which is `D:\OpenSpan`). The GUI's separate
@@ -176,13 +179,21 @@ Windows input portal (openspan_portal.py, captures at the screen edge)
   entry script); every module switches its path anchor from `__file__` to
   `sys.executable` under `sys.frozen`. Built `--noconsole` + unflagged →
   unelevated, no console flash. The exe / `build/` / `dist/` are gitignored.
-- **Why a renamed interpreter (`openspanw.exe`):** `C:\Python313\pythonw.exe`
-  carries a `RUNASADMIN` AppCompatFlags layer that forces elevation of the
-  unsigned interpreter, which trips Windows' shell reputation gate ("an
-  administrator has blocked this app" — independent of the UAC prompt setting).
-  A same-directory unflagged copy (`Copy-Item pythonw.exe openspanw.exe`) runs
-  unelevated → no block. OpenSpan needs no admin (VBoxManage / ssh / shutdown /
-  subprocess all work unelevated).
+- **Why the launcher resolves interpreters dynamically (was `openspanw.exe`):**
+  a renamed-interpreter copy (`openspanw.exe`) was once used because
+  `pythonw.exe` under some installs carries a `RUNASADMIN` AppCompatFlags
+  layer that forces elevation of the unsigned interpreter and trips Windows'
+  shell reputation gate ("an administrator has blocked this app"). That trick
+  hardcodes an install path (`C:\Python313\...`), so `OpenSpan.bat` now picks
+  the first *working* GUI interpreter at launch instead: pyw.exe (Python
+  Launcher) → pythonw.exe on PATH → python.exe on PATH (Store stub skipped) →
+  newest registered PythonCore install (pythonw preferred), each validated
+  with `import tkinter`. No renamed binaries, no path assumptions, no PATH
+  edits. OpenSpan itself needs no admin (VBoxManage / ssh / shutdown /
+  subprocess all work unelevated); for UIPI compatibility with elevated
+  apps on the desktop run the launcher *as administrator* (right-click →
+  Run as administrator, or `Start-Process -Verb RunAs`), which the GUI's
+  NOT ADMIN indicator covers.
 - **Do not put the launcher in a OneDrive-synced folder** — that was a false
   lead, but OneDrive placeholders add their own friction; keep launchers local
   (Start Menu / D: drive).

build_exe.py

@@ -1,13 +1,16 @@
 #!/usr/bin/env python3
 """Build OpenSpan into a single-file OpenSpan.exe (PyInstaller).
 
-    C:\\Python313\\python.exe D:\\OpenSpan\\build_exe.py
+    py -3 build_exe.py            # any local Python 3.x works, from the repo
+    :: or: python build_exe.py
 
 Produces D:\\OpenSpan\\OpenSpan.exe. Because the app anchors all its data on
 the executable's folder (sys.executable when frozen), the exe is dropped
 straight into D:\\OpenSpan\\ next to the configs/keys/scripts it already uses
--- nothing else to assemble. No console window; unelevated (so it dodges the
-same shell-reputation gate the openspanw.exe trick was created for).
+-- nothing else to assemble. No console window; unelevated, so it dodges
+the same shell-reputation gate that a RUNASADMIN-flagged pythonw.exe would
+trip (OpenSpan.bat resolves the raw .py interpreter dynamically today: no
+renamed openspanw.exe needed).
 """
 import os
 import shutil