docs: add Config XML field notes from real-project edits

[s31teg]

Summary

Adds docs/knowledge/config-xml-field-notes.md, a reference for agents and contributors who edit .Loxone files. It records behaviour observed while editing a real house project (Loxone Config 17.2) that the official block docs in docs/kb/ don't cover, or describe under different names. Every edit was uploaded to and checked on a Miniserver. AGENTS.md links the new page under "Key files for config editing".

What it covers

• Document save stamp (Date / DateS): Config tells programs apart by this stamp, not by content, so an edited file that keeps the old stamp is treated as the program already on the Miniserver and the edits are lost on Connect. The page also gives the DateS epoch and a worked example.
• Wire flags: FLG="2" marks cross-page wires and FLG="1" marks links that Config manages itself. References to devices and virtual inputs are wired from AQ, not Q.
• User object permissions: <PH> / <PRM> entries, and why a webhook call to a new virtual input gets HTTP 403.
• Lighting Controller:
  • XML connector names mapped to the doc abbreviations (EnMove = DisP, MoveOn = Met, MoveIgnore = Pto, …).
  • Mood pulses longer than 0.2 s mix the mood in instead of selecting it.
  • LSConfig motion rows, including the 778 catch-all.
• Automatic Shading:
  • XML names mapped to the docs (EnAutoShade = DisSp, DirTol / DirTol2 = Dts / Dte, Back = Rd, …).
  • EndUp / EndDown cancel the sun automatic.
  • The end action only runs at the computed "shading until" time.
• Other blocks:
  • the remanence encoding;
  • combined window contact status values;
  • presence block sensor links;
  • the linked-functions flag;
  • favourites and app rating.
• Tracker event log: how to add a Tracker and OutputRefLM log references, for tracing where a signal stops.
• Cosmetic quirks: Config 17.2 shows "INVALID FORMULA" on working formulas, and replaces % in titles with _.

Testing

Documentation only. cargo fmt --check, cargo clippy -- -D warnings, cargo build --release and cargo test pass.