Add v0.1 scaffold: tree-sitter-p8-cart grammar and Zed extension

The grammar parses the .p8 cartridge container ( header, version, and
the named __lua__/__gfx__/__gff__/__label__/__map__/__sfx__/__music__
sections, plus a fallback unknown_section ). The Zed language definition
hands the __lua__ body to Zed's built-in Lua via injections.scm, so
non-dialect Lua code highlights correctly today; PICO-8-specific syntax
(?, +=, !=, single-line if, etc.) will fall back to error highlighting
in those regions only — see README roadmap for the dialect grammar fork.

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

package-lock.json

@@ -0,0 +1,30 @@
+{
+  "name": "tree-sitter-p8-cart",
+  "version": "0.0.1",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "tree-sitter-p8-cart",
+      "version": "0.0.1",
+      "license": "0BSD",
+      "devDependencies": {
+        "tree-sitter-cli": "^0.24.7"
+      }
+    },
+    "node_modules/tree-sitter-cli": {
+      "version": "0.24.7",
+      "resolved": "https://registry.npmjs.org/tree-sitter-cli/-/tree-sitter-cli-0.24.7.tgz",
+      "integrity": "sha512-o4gnE82pVmMMhJbWwD6+I9yr4lXii5Ci5qEQ2pFpUbVy1YiD8cizTJaqdcznA0qEbo7l2OneI1GocChPrI4YGQ==",
+      "dev": true,
+      "hasInstallScript": true,
+      "license": "MIT",
+      "bin": {
+        "tree-sitter": "cli.js"
+      },
+      "engines": {
+        "node": ">=12.0.0"
+      }
+    }
+  }
+}