Make the component installable as a git dependency

`component/package.json` describes the built component as a package
(`@element-hq/element-call-component`: entry, stylesheet subpath, types,
peer dependencies) so that a host can depend on
`github:element-hq/element-call#<ref>&path:/component`. Its `prepare`
script builds on install, since nothing is published yet.

For that the component build now lands in `component/dist` instead of the
repository's `dist`, and `pnpm build:component` also emits the type
declarations (`component/tsconfig.build.json`, `build:component:types`),
which previously had to be produced by hand.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

component/package.json

@@ -0,0 +1,42 @@
+{
+  "name": "@element-hq/element-call-component",
+  "version": "0.0.0",
+  "description": "Element Call as a React component. Consumed straight from the repository as a git dependency (github:element-hq/element-call#<ref>&path:/component): the host's package manager runs `prepare`, which builds `dist/`.",
+  "license": "SEE LICENSE IN ../README.md",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/element-hq/element-call",
+    "directory": "component"
+  },
+  "type": "module",
+  "devEngines": {
+    "packageManager": {
+      "name": "pnpm"
+    }
+  },
+  "files": [
+    "dist"
+  ],
+  "main": "./dist/element-call.js",
+  "module": "./dist/element-call.js",
+  "types": "./dist/types/component/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/types/component/index.d.ts",
+      "default": "./dist/element-call.js"
+    },
+    "./style.css": "./dist/element-call.css"
+  },
+  "sideEffects": [
+    "*.css"
+  ],
+  "scripts": {
+    "prepare": "cd .. && pnpm install --frozen-lockfile && pnpm build:component"
+  },
+  "peerDependencies": {
+    "livekit-client": "^2.18.1",
+    "matrix-js-sdk": "*",
+    "react": "^19",
+    "react-dom": "^19"
+  }
+}

component/pnpm-lock.yaml

@@ -0,0 +1,9 @@
+lockfileVersion: '9.0'
+
+settings:
+  autoInstallPeers: false
+  excludeLinksFromLockfile: false
+
+importers:
+
+  .: {}

component/pnpm-workspace.yaml

@@ -0,0 +1,14 @@
+# Makes `component/` a pnpm project of its own rather than a directory inside
+# the repository's workspace. That matters when a host installs the component
+# straight from this repository (`github:element-hq/element-call#…&path:/component`):
+# pnpm prepares such a dependency by running `pnpm install` in this directory,
+# and only a project root gets its `prepare` script (see package.json) run, which
+# is what builds `dist/`. Inside the repository's own workspace the install
+# would silently target the repository instead and build nothing.
+#
+# Consequence for development: pnpm commands run from within this directory see
+# this project, not the repository; run them from the repository root.
+
+# Nothing to install here: the peers in package.json are the host's, and the
+# build runs against the repository's own node_modules (see `prepare`).
+autoInstallPeers: false

component/tsconfig.build.json

@@ -0,0 +1,20 @@
+{
+  // Declaration output for the component package (`pnpm build:component:types`).
+  // The root tsconfig only type-checks; this one emits `.d.ts` files, and nothing
+  // else, for everything the component's entry point reaches. The layout under
+  // `dist/types` mirrors the repository (`component/index.d.ts`, `src/…`), which
+  // is what `package.json` points its `types` at.
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "noEmit": false,
+    "emitDeclarationOnly": true,
+    "declaration": true,
+    "declarationMap": false,
+    "rootDir": "..",
+    "outDir": "./dist/types"
+  },
+  // The entry point, plus the ambient declarations (CSS modules, `?react` SVGs,
+  // `import.meta.env`, …) that the sources it reaches rely on.
+  "include": ["./index.tsx", "../src/@types/*.d.ts"],
+  "exclude": []
+}