Two bugs surfaced while investigating camera reconnect behaviour in #925.
The camera page briefly displayed "Reconnecting attempt 6 of 5" before
giving up, because the attempt counter could be incremented to the
maximum while the reconnect banner was still rendering. The displayed
value is now clamped to the configured maximum.
Every failed ffmpeg spawn logged the full ~20-line ffmpeg version,
configuration, and lib* banner, producing hundreds of lines of noise
per failed camera click (one reported click produced 555 log lines
across 30 retries). A new _summarize_ffmpeg_stderr helper strips the
banner and caps output at the last 10 meaningful lines, applied at
all three stderr log sites (immediate-failure, stream-ended,
read-timeout). Covered by unit tests for empty input, banner
stripping, line cap, blank-line filtering, and banner-only input.
The underlying "camera service stops accepting connections after
prolonged uptime" behaviour in the X1C firmware is still under
investigation — these two fixes are independent of that root cause.
