feat: single-command Docker startup, fix UI bugs, add Selenium tests

- Add `make up` / `make up DEV=1` for one-command Docker startup with
  optional hot-reload via docker-compose.dev.yml overlay
- Add `timmy up --dev` / `timmy down` CLI commands
- Fix cross-platform font resolution in creative assembler (7 test failures)
- Fix Ollama host URL not passed to Agno model (container connectivity)
- Fix task panel route shadowing by reordering literal routes before
  parameterized routes in swarm.py
- Fix chat input not clearing after send (hx-on::after-request)
- Fix chat scroll overflow (CSS min-height: 0 on flex children)
- Add Selenium UI smoke tests (17 tests, gated behind SELENIUM_UI=1)
- Install fonts-dejavu-core in Dockerfile for container font support
- Remove obsolete docker-compose version key
- Bump CSS cache-bust to v4

833 unit tests pass, 15 Selenium tests pass (2 skipped).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.dev.yml

@@ -0,0 +1,23 @@
+# ── Timmy Time — Dev-mode overlay ────────────────────────────────────────────
+#
+# Enables hot-reload: Python, template, and CSS changes auto-apply.
+#
+# Usage:
+#   make up DEV=1
+#   # or directly:
+#   docker compose -f docker-compose.yml -f docker-compose.dev.yml up -d --build
+
+services:
+  dashboard:
+    command:
+      - uvicorn
+      - dashboard.app:app
+      - --host=0.0.0.0
+      - --port=8000
+      - --reload
+      - --reload-dir=/app/src
+      - --reload-include=*.html
+      - --reload-include=*.css
+      - --reload-include=*.js
+    environment:
+      DEBUG: "true"