Add per-file partial-credit progress to the runtime metrics

[ptr727]

Summary

Runtime metrics v2 (issue #848 follow-on). v1 credited a file's whole byte weight only at completion, so progress.ratio staircased and eta.seconds jumped. v2 folds partial credit for in-flight files: each in-flight file carries a fraction in [0,1] driven by its currently-running long tool, and ComputeProgress adds Sum(inflight_bytes * fraction) to the completed total. Metrics-only, no state file, no per-file detail exposed.

Changes

• Metrics: per-file FileSink (byte weight + atomic permyriad fraction), a lock-free in-flight registry, and a ThreadLocal current-file sink captured at each tool call site so a CliWrap pipe-thread closure can report progress without touching the ThreadLocal. Completion still credits the whole size (no double counting); the sink is removed and the ThreadLocal cleared in the driver finally.
• MediaTool.ExecuteStreamStdOut: streams stdout line-by-line for progress while capturing stderr for failure logging.
• Instrumented long ops only: ffprobe full-file scan (pts/duration), ffmpeg re-encode (-progress pipe:1), HandBrake re-encode (--json Working.Progress). Fast remux/copy/setts stay at 0 until completion.
• Docs: README Runtime Metrics section notes partial-credit progress + dotnet-counters/dotnet-monitor recipes; HISTORY 3.22 entry. All README/HISTORY inline URIs converted to reference-style links, grouped shields/internal/external and alphabetized.

No version bump (stays 3.22). No new NuGet package (Metrics + ConcurrentDictionary + ThreadLocal are BCL).

Verification

• Build analyzer-clean, 0 warnings under TreatWarningsAsErrors/AnalysisMode=All
• dotnet format style --verify-no-changes --severity=info clean, CSharpier clean
• 241/241 tests pass, incl. new fold-math and tool progress-parser tests
• markdownlint + cspell clean

Follow-up (not in this PR)

Develop Docker build, then regression testing with dotnet-counters monitor --counters PlexCleaner.Process to confirm progress.ratio climbs smoothly and eta.seconds decays smoothly during real scans/re-encodes.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This pull request enhances PlexCleaner’s runtime metrics (System.Diagnostics.Metrics) to report smoother weighted progress by awarding partial credit to in-flight files based on long-running tool progress, improving progress.ratio and eta.seconds stability during scans and re-encodes.

Changes:

• Adds a per-file in-flight “sink” (bytes + atomic fraction) and folds partial in-flight credit into Metrics.ComputeProgress.
• Streams tool progress output for ffmpeg (-progress pipe:1) and HandBrake (--json) and parses progress lines to update the current file’s fraction.
• Updates docs (README/HISTORY) to describe partial-credit progress and standardizes links to reference-style; adds/updates unit tests for progress parsing and progress folding.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
README.md	Documents partial-credit runtime progress; converts many links to reference-style and reorganizes link refs.
HISTORY.md	Updates v3.22 notes to mention partial-credit progress and dotnet-monitor compatibility; converts links to reference-style.
PlexCleaner/Metrics.cs	Introduces per-file FileSink, in-flight registry, ThreadLocal current sink, and partial-credit folding in ComputeProgress.
PlexCleaner/MediaTool.cs	Adds ExecuteStreamStdOut and an error-logging overload to support stdout progress streaming with stderr capture.
PlexCleaner/ProcessDriver.cs	Passes per-file byte size into Metrics.FileStarted to seed in-flight weighting.
PlexCleaner/ProcessFile.cs	Reports ffprobe packet-scan progress as a fraction of media duration.
PlexCleaner/Process.cs	Seeds per-file duration (microseconds) for ffmpeg progress fraction computation.
PlexCleaner/FfMpegBuilder.cs	Adds -progress pipe:1 builder helper.
PlexCleaner/FfMpegTool.cs	Parses ffmpeg -progress lines and reports per-file progress fraction during encode.
PlexCleaner/HandBrakeBuilder.cs	Adds --json global option helper.
PlexCleaner/HandBrakeTool.cs	Enables --json, parses HandBrake progress, and reports per-file progress fraction while streaming stdout.
PlexCleanerTests/MetricsTests.cs	Updates tests for new FileStarted(size) and adds coverage for partial-credit folding and clamping.
PlexCleanerTests/ToolProgressParsingTests.cs	Adds unit tests for ffmpeg and HandBrake progress line parsing.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated no new comments.