chore(ci): add typecheck scripts for local TypeScript verification

Adds a yarn typecheck script in the repository root and per-package typecheck
scripts that run tsc --noEmit in each TypeScript workspace (web, backend,
db, schemas, shared). Mirrors the existing test/lint conventions: root uses
yarn workspaces foreach --all --topological, per-package scripts execute
the same TypeScript compiler invocation in isolation.

A new .github/workflows/typecheck.yml CI workflow is intentionally NOT added
in this commit because running tsc --noEmit on the current main surfaces
~175 latent type errors in the web package (test fixtures referencing
schema-drift columns added to migrations 20260702000000 and 20260702000001
but not yet declared in schema.prisma). A follow-up PR will fix the
schema-drift, update test fixtures, then add the CI workflow.

Mirrors CONTRIBUTING.md 'Developer tooling' / 'Bug fixes' guidance: pure
additive tooling, no source code changes, no new dependencies.

Refs #1437

Author: Harsh23Kashyap

package.json

@@ -7,6 +7,7 @@
         "build": "cross-env SKIP_ENV_VALIDATION=1 yarn workspaces foreach --all --topological run build",
         "test": "yarn workspaces foreach --all --topological run test",
         "lint": "yarn workspaces foreach --all --topological run lint",
+        "typecheck": "yarn workspaces foreach --all --topological run typecheck",
         "dev": "concurrently --kill-others --names \"zoekt,worker,web,schemas\" 'yarn dev:zoekt' 'yarn dev:backend' 'yarn dev:web' 'yarn watch:schemas'",
         "with-env": "cross-env PATH=\"$PWD/bin:$PATH\" dotenv -e .env.development -c --",
         "dev:zoekt": "yarn with-env zoekt-webserver -index .sourcebot/index -rpc",

packages/backend/package.json

@@ -8,6 +8,7 @@
         "dev:watch": "tsc-watch --preserveWatchOutput --onSuccess \"yarn dev\"",
         "dev": "node ./dist/index.js",
         "build": "tsc",
+        "typecheck": "tsc --noEmit",
         "test": "cross-env SKIP_ENV_VALIDATION=1 vitest --config ./vitest.config.ts"
     },
     "devDependencies": {

packages/db/package.json

@@ -5,6 +5,7 @@
     "private": true,
     "scripts": {
         "build": "yarn prisma:generate && tsc",
+        "typecheck": "tsc --noEmit",
         "postinstall": "yarn build",
         "prisma:generate": "prisma generate",
         "prisma:generate:watch": "prisma generate --watch",

packages/schemas/package.json

@@ -4,6 +4,7 @@
     "private": true,
     "scripts": {
         "build": "yarn generate && tsc",
+        "typecheck": "tsc --noEmit",
         "generate": "tsx tools/generate.ts",
         "watch": "nodemon --watch ../../schemas -e json -x 'yarn build'",
         "postinstall": "yarn build"

packages/shared/package.json

@@ -5,6 +5,7 @@
     "private": true,
     "scripts": {
         "build": "tsc",
+        "typecheck": "tsc --noEmit",
         "build:watch": "tsc-watch --preserveWatchOutput",
         "postinstall": "yarn build",
         "test": "vitest --config ./vitest.config.ts",

packages/web/package.json

@@ -7,6 +7,7 @@
     "build": "cross-env SKIP_ENV_VALIDATION=1 next build",
     "start": "next start",
     "lint": "cross-env SKIP_ENV_VALIDATION=1 eslint .",
+    "typecheck": "tsc --noEmit",
     "test": "cross-env SKIP_ENV_VALIDATION=1 vitest",
     "openapi:generate": "tsx tools/generateOpenApi.ts",
     "generate:protos": "proto-loader-gen-types --includeComments --longs=Number --enums=String --defaults --oneofs --grpcLib=@grpc/grpc-js --keepCase --includeDirs=../../vendor/zoekt/grpc/protos --outDir=src/proto zoekt/webserver/v1/webserver.proto zoekt/webserver/v1/query.proto",