Wire bake orchestrator and CLI

Connects scan + lock + pack + write into the full pipeline. CLI entry
parses args, dispatches to bake(), prints summary or error. Five
integration tests cover fresh bake, lock-aware ID preservation,
deleted-tile tracking, oversize hard-fail, and bit-identical
determinism across re-bakes.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/bake-deleted-tile.test.js

@@ -0,0 +1,38 @@
+const { test } = require('node:test');
+const assert = require('node:assert');
+const path = require('node:path');
+const fs = require('node:fs');
+const os = require('node:os');
+const { bake } = require('../src/bake');
+
+test('bake-deleted: missing source moves ID to deleted[]', async () => {
+    const srcDir = fs.mkdtempSync(path.join(os.tmpdir(), 'atlas-src-'));
+    const outDir = fs.mkdtempSync(path.join(os.tmpdir(), 'atlas-out-'));
+    try {
+        // Copy only grass + stone from fixture (omit water)
+        const FIX = path.resolve(__dirname, 'fixtures/small-fresh');
+        fs.copyFileSync(path.join(FIX, 'grass_diffuse.png'), path.join(srcDir, 'grass_diffuse.png'));
+        fs.copyFileSync(path.join(FIX, 'stone_diffuse.png'), path.join(srcDir, 'stone_diffuse.png'));
+
+        // Pre-existing lock has all 3 names
+        fs.writeFileSync(
+            path.join(outDir, 'tiles.atlas.lock.json'),
+            JSON.stringify({
+                atlas_id: 'small_demo',
+                bindings: { grass: 1, stone: 2, water: 3 },
+                deleted: [],
+                next_id: 4,
+            }, null, 2),
+        );
+
+        await bake({ inDir: srcDir, outDir, atlasId: 'small_demo', tileSize: 32 });
+
+        const lock = JSON.parse(fs.readFileSync(path.join(outDir, 'tiles.atlas.lock.json'), 'utf8'));
+        assert.strictEqual(lock.bindings.water, undefined);
+        assert.deepStrictEqual(lock.deleted, [3]);
+        assert.strictEqual(lock.next_id, 4);  // not advanced
+    } finally {
+        fs.rmSync(srcDir, { recursive: true, force: true });
+        fs.rmSync(outDir, { recursive: true, force: true });
+    }
+});