feat: add About well to settings with build info and debug easter egg (#145)

## Summary

Add a new well at the bottom of the settings view displaying application info (license, author, version, build date, git commit hash linked to Gitea), and an easter egg that reveals a debug mode toggle after clicking the version number 10 times.

## Changes

- **`src/popup/index.html`**: Added About well with license, author, version, build date, and linked commit hash. Added hidden debug well with debug mode toggle.
- **`src/popup/views/settings.js`**: Populate About well from build-time constants. Implement version click counter (10 clicks reveals debug well). Wire up debug mode toggle to state and runtime logger.
- **`src/shared/buildInfo.js`** (new): Module exporting build-time constants (`BUILD_VERSION`, `BUILD_LICENSE`, `BUILD_AUTHOR`, `BUILD_COMMIT`, `BUILD_DATE`, `GITEA_COMMIT_URL`) injected by esbuild define.
- **`build.js`**: Read git commit hash (short + full) and version from package.json, pass as esbuild `define` constants. Also reads `GIT_COMMIT_SHORT`/`GIT_COMMIT_FULL` env vars for Docker builds.
- **`Dockerfile`**: Accept `GIT_COMMIT_SHORT` and `GIT_COMMIT_FULL` build args, set as env vars for the build step.
- **`Makefile`**: Pass git commit hashes as Docker build args.
- **`src/shared/state.js`**: Add `debugMode` boolean to state (persisted).
- **`src/shared/log.js`**: Add runtime debug flag that supplements the compile-time `DEBUG` constant. Debug mode toggle updates this flag immediately.

closes #144

Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Co-authored-by: clawbot <clawbot@sneak.cloud>
Co-authored-by: user <user@Mac.lan guest wan>
Co-authored-by: clawbot <clawbot@eeqj.de>
Co-authored-by: sneak <sneak@sneak.berlin>
Reviewed-on: #145
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

src/popup/index.js

@@ -1,18 +1,14 @@
 // AutistMask popup entry point.
 // Loads state, initializes views, triggers first render.
 
-const { DEBUG } = require("../shared/constants");
-const {
-    state,
-    saveState,
-    loadState,
-    currentNetwork,
-} = require("../shared/state");
+const { state, saveState, loadState } = require("../shared/state");
+const { setRuntimeDebug } = require("../shared/log");
 const { refreshPrices } = require("../shared/prices");
 const { refreshBalances } = require("../shared/balances");
 const {
     $,
     showView,
+    updateDebugBanner,
     setRenderMain,
     pushCurrentView,
     goBack,
@@ -209,21 +205,11 @@ async function init() {
     await loadState();
     applyTheme(state.theme);
 
-    const net = currentNetwork();
-    if (DEBUG || net.isTestnet) {
-        const banner = document.createElement("div");
-        banner.id = "debug-banner";
-        if (DEBUG && net.isTestnet) {
-            banner.textContent = "DEBUG / INSECURE [TESTNET]";
-        } else if (net.isTestnet) {
-            banner.textContent = "[TESTNET]";
-        } else {
-            banner.textContent = "DEBUG / INSECURE";
-        }
-        banner.style.cssText =
-            "background:#c00;color:#fff;text-align:center;font-size:10px;padding:1px 0;font-family:monospace;position:sticky;top:0;z-index:9999;";
-        document.body.prepend(banner);
-    }
+    // Sync runtime debug flag from persisted state before first render
+    setRuntimeDebug(state.debugMode);
+
+    // Create the debug/testnet banner if needed (uses runtime debug state)
+    updateDebugBanner();
 
     // Auto-default active address
     if (