docs: F1.31 where files are kept, and F1.32 logging and telemetry settings (specs)

[gx1400]

Spec for #306 (0.6.0).

Agreed:

• What About lists: a Files part with the folders only (Settings, Data, Map tiles, Logs, Defaults for every user). Each has a Copy button.
  • A folder moved in configuration says so.
  • A folder that doesn't exist yet says "not created yet".
• A rolling log on the desktop, in Data/logs: aprsmap.log plus up to 4 older files, 2 MB each.
• Gateway: only a signed-in operator sees the server's folders. Viewers get a note that their layout is kept in their browser, and the gateway's log stays the container output.

Also in the spec:

• Nothing secret is logged: no passcodes, passwords or session cookies.
• Message text is logged at Debug only.
• Each part reports its own folder: the engine, the tile service and the host each report theirs, and the engine collects them. AprsMap.Core therefore needn't know about tiles.

For review:

• Decision 4: our own small file logger instead of Serilog.
• Decision 5: 5 files × 2 MB.
• Decision 6: Open folder left for later.

The F1.31 scope row is in #305, which now links this spec.

[gx1400]

Added F1.32 Logging and telemetry settings (#310). F1.31's log-file part moved there, so F1.31 is now about the About › Files list.

Agreed (one at a time):

1. Where: Settings › Logging, with the environment winning.
2. What to log: an overall level, a level per area, and two privacy switches (every packet, message texts).
3. Log file location: on by default on the desktop, in Data/logs, with the folder changeable; off on a gateway.
4. Retention: a file per day, a maximum size, days kept, and a total cap.
5. OTLP: a list of targets.
6. Headers: masked and write-only.

For review: decisions 7–10 in F1.32:

• Map tiles default to Warnings; your test log was almost all tile requests.
• Our own file logger rather than Serilog.
• The defaults: 10 MB, 14 days, 100 MB.
• UTC dates in the file names.

F1.31's open decision is Open folder, left for later.

[gx1400]

F1.32's review decisions are agreed:

• Decision 7: Map tiles at Warnings.
• Decision 8: Serilog's file sink as a plain provider in AprsMap.Hosting. Microsoft's logging keeps the filters.
• Decision 9: 10 MB, 14 days, 100 MB.
• Decision 10: UTC file dates.

The sink rolls by local time, so the host rebuilds it at UTC midnight with the dated name. Retention by days and by the total cap is the host's cleanup. The spec now also says why the file and OTLP sit side by side behind ILogger: .NET's OTLP exporter only sends over the network.