fix: minor correctness and performance bugs

[TheOfficialDragone]

No description provided.

[TheOfficialDragone]

What this PR fixes

Four correctness and performance bugs found by static code review. None cause crashes, but two produce silently wrong results.

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1. RTKBaseConfigManager.expand_path() — str.strip() is not prefix removal (RTKBaseConfigManager.py)

# Before (wrong)
datadir.strip("$BASEDIR/")

str.strip(chars) removes any character in the set from both ends of the string — it is not a prefix-removal operation. For a value like "$BASEDIR/data" it works by coincidence, but for any path whose trailing characters overlap with the set ($, B, A, S, E, D, I, R, /) the path is silently truncated.

# After (correct, Python 3.9+ — already the minimum)
datadir.removeprefix("$BASEDIR/")

Same fix applied to logdir.

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2. LogManager.updateAvailableLogs() — sort() called inside the loop (LogManager.py)

# Before: O(n² log n)
for log in glob(self.log_path + "/*"):
    self.available_logs.append(...)
    self.available_logs.sort(...)   # called on every iteration

# After: O(n log n)
for log in glob(self.log_path + "/*"):
    self.available_logs.append(...)

self.available_logs.sort(...)       # called once after the loop

With hundreds of log files on a Raspberry Pi the difference is measurable.

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3. network_infos.get_interfaces_infos() — nmcli.device.show() called twice per interface (network_infos.py)

# Before: two subprocess forks per interface
conn_name = get_conn_name(k)                    # calls nmcli.device.show(k) internally
device_info["hwaddr"] = nmcli.device.show(k).get('GENERAL.HWADDR')   # second call

# After: one call, both values extracted from the same result
device_show = nmcli.device.show(k)
conn_name = device_show.get("GENERAL.CONNECTION")
device_info["hwaddr"] = device_show.get("GENERAL.HWADDR")

Also wraps the call in try/except nmcli.NotExistException for consistency with get_conn_name().

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4. server.update_settings() — unguarded list.pop() on socket input (server.py)

# Before: IndexError if client sends empty list
source_section = json_msg.pop().get("source_form")

# After: early return on empty/malformed input
if not json_msg:
    print("ERROR: update_settings received empty message")
    return
source_section = json_msg.pop().get("source_form")

Under gevent, an unhandled IndexError inside a socket handler is swallowed silently, leaving the handler dead for the rest of the session.

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How to test

• Set datadir or logdir to a path with characters that overlap the old strip set (e.g. $BASEDIR/rinex_data) and confirm the expanded path is correct
• Open the Logs page with a large number of log files and confirm the list loads correctly and is sorted
• Open the Settings page and confirm network interfaces show the correct connection name and MAC address with a single nmcli call
• Send a malformed form data socket event (empty array) and confirm the server does not crash