Split server.mjs into modules: db, views, routes

server.mjs mixed SQL schema, HTML-rendering functions, and route
handling in one 476-line file. Split by concern:

- src/db.mjs — schema + migrations (openDb())
- src/views.mjs — pure render functions: layout, incidentForm,
  publicMarkdown/Incident/Detail, no db or network access
- src/style.mjs — the stylesheet, now genuinely shared instead of
  duplicated (receipts.mjs's /events page had its own near-copy,
  which is exactly what let their <nav> definitions drift out of
  sync a few commits ago)
- src/http-utils.mjs — form()/redirect(), used by more than one route
- src/routes/incidents.mjs — the private notebook + Git inbox +
  publish/unpublish, auth-gated once at the top instead of per-route
- src/routes/public-failures.mjs — the read-only /api/v1/public/failures*
  projection

server.mjs is now 79 lines of composition: open the db, build each
route module, wire the dispatch order, listen.

Also dropped the old POST /api/receipts endpoint and its `receipts`
table — dead since the v1 events API replaced it, already flagged as
"scheduled for removal" in the README.

Verified behavior is unchanged, not just "looks the same": full route
smoke test (401/200/404 in the right places, incident create→publish→
public-projection round trip, receipt ingestion), tests pass, and
before/after screenshots of every page are pixel-identical.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

package.json

@@ -1 +1,17 @@
-{"name":"trace","version":"0.1.0","private":true,"type":"module","scripts":{"dev":"node --watch --env-file-if-exists=.env src/server.mjs","start":"node --env-file-if-exists=.env src/server.mjs","test":"node --test","build":"node --check src/server.mjs","format":"npx --yes prettier@3.9.5 --write \"src/*.mjs\" \"test/*.mjs\"","format:check":"npx --yes prettier@3.9.5 --check \"src/*.mjs\" \"test/*.mjs\""},"engines":{"node":">=24"}}
+{
+    "name": "trace",
+    "version": "0.1.0",
+    "private": true,
+    "type": "module",
+    "scripts": {
+        "dev": "node --watch --env-file-if-exists=.env src/server.mjs",
+        "start": "node --env-file-if-exists=.env src/server.mjs",
+        "test": "node --test",
+        "build": "node --check src/server.mjs",
+        "format": "npx --yes prettier@3.9.5 --write \"src/**/*.mjs\" \"test/*.mjs\"",
+        "format:check": "npx --yes prettier@3.9.5 --check \"src/**/*.mjs\" \"test/*.mjs\""
+    },
+    "engines": {
+        "node": ">=24"
+    }
+}