split-view phase 3: rich per-line instruction region highlight

The Ghidra "region band": moving the pseudocode cursor now lights up EVERY
instruction that C line owns, not just one.

* server/patch_server.py: new decomp_map tool — sweeps cfunc.get_line_item across
  each pseudocode line's columns and collects the ea from each item's dstr()
  ('EA: desc', matching the /*ea*/ marker source so it aligns with the display
  lines). Returns {addr, lines:[{ea, eas:[...]}]}. (First tried item.get_ea(),
  which reports a different ea and didn't align — dstr() is the right source.)
* domain: Program.decomp_map(ea) -> per-line ea lists, cached by name-gen.
* app: _load_split_map fetches it off-thread into _split_eamap/_split_ea2line;
  _sync_split bands the full instruction region for a C line (decomp drives) and
  uses the exact ea->line inverse (listing drives), falling back to the single
  marker until the map lands. Maps cleared on leaving split.

Pilot split_view gains: decomp_map returns/aligns with the markers, and a
multi-instruction C line bands >1 listing row (13/13). Full suite 154/2-flake.
The idalib spike ran on the pilot's own worker (the standalone worker kept
getting reaped in this sandbox).

1 files changed, 9 insertions, 3 deletions

diff --git a/docs/SPLIT_VIEW.md b/docs/SPLIT_VIEW.md
index 740ae90..a8546fa 100644
--- a/docs/SPLIT_VIEW.md
+++ b/docs/SPLIT_VIEW.md
@@ -78,9 +78,15 @@ decomp→listing uses `ListingModel.ensure_ea`. Tab re-links from the new driver
 Still single-ea per line (one instruction highlighted); the region comes in
 phase 3.
 
-**Phase 3 — rich highlight.** `decomp_map` custom tool (line → ea-set) stored on
-`Decompilation`; highlight the whole instruction range of a C line; tighten the
-reverse map. One custom tool + an idalib spike to confirm the sweep works.
+**Phase 3 — rich highlight. DONE.** `decomp_map` custom tool
+(`server/patch_server.py`) sweeps `cfunc.get_line_item` across every column of
+each pseudocode line and collects the EAs from each item's `dstr()` (`'EA: desc'`
+— the same source as the `/*ea*/` marker, so it aligns). `Program.decomp_map(ea)`
+returns the per-line ea lists (cached by name-gen); the app loads it async into
+`_split_eamap` / `_split_ea2line` and `_sync_split` bands the **whole** instruction
+region of a C line (and uses the exact ea→line inverse for the reverse). Falls
+back to the single marker until the map lands. Verified on the pilot's real worker
+(alignment + multi-instruction region band).
 
 **Phase 4 — polish.** Navigation keeps both panes on the same function; loop/goto
 edge cases; decompile-failed fallback; min-width gate + resize; split state in