chore: ignore dev-note artifacts, start alpha versioning at 0.1.0-alpha.1

.gitignore now excludes everything that is not part of the app itself:
memory/, research/, TODO-Feature-Docs/, HANDOFF*/GAMEPLAN notes, .codex/,
.claude/ and logs. Version begins the alpha line at 0.1.0-alpha.1 across
the cargo workspace, package.json and tauri.conf.json.

.gitignore

@@ -1,5 +1,18 @@
+# Build output
 target/
 node_modules/
 dist/
 src-tauri/gen/
+
+# Logs / scratch
 *.log
+nohup.out
+
+# Dev notes, research and planning artifacts — not part of the app
+memory/
+research/
+TODO-Feature-Docs/
+HANDOFF*.md
+GAMEPLAN.md
+.codex/
+.claude/