Add Phase 1 SQL support with DataFusion and Substrait

Implements end-to-end SQL query pipeline for simple SELECT queries:

Compile-time: MergedSelectionMap → DataFusion LogicalPlan → Substrait binary
Runtime: Substrait plan → isograph-server execution → Arrow IPC response

New components:
- crates/sql_network_protocol: NetworkProtocol impl; LogicalPlan builder and
  Substrait serialization; parses SQL schema into Isograph's type model
- crates/sql_lang_types, crates/sql_schema_parser: SQL-specific language types
  and DDL parser
- crates/isograph_server: Axum HTTP server with /query endpoint
- demos/sqlite-demo: end-to-end Vite+React demo using Star Wars planets SQLite
- test-fixtures/databases: SQLite schema and init scripts for Phase 1–3
- E2E Playwright tests for the full pipeline

Type system: widen NetworkResponseObject from branded-key mapped type to plain
string index signature so SQL-generated types (e.g. { id: number, name: string })
satisfy the constraint without @ts-ignore. SQL numeric IDs accepted via
id?: DataId | number. Zero breaking change for existing GraphQL code.

Compiler: add readonly modifiers and field-name quoting to SQL-generated
raw_response_type.ts files.

Build fixes: update swc workspace deps for serde 1.0.220+ compatibility,
fix clippy needless_return, add protoc to CI for substrait code generation,
update pnpm lockfile, fix prettier and oxlint issues.

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

Author: edmondop

.github/workflows/build-cli.yml

@@ -66,6 +66,15 @@ jobs:
         with:
           packages: musl-tools # provides musl-gcc
           version: 1.0
+      - name: Install protoc (Linux)
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y protobuf-compiler
+      - name: Install protoc (macOS)
+        if: runner.os == 'macOS'
+        run: brew install protobuf
+      - name: Install protoc (Windows)
+        if: runner.os == 'Windows'
+        run: choco install protoc
       - name: 'Build isograph_cli with cargo (${{inputs.target}})'
         run: pnpm exec turbo ${{ inputs.cross && 'cross' || 'build-compiler' }} -- --target ${{ inputs.target }} --release
       - uses: actions/upload-artifact@v4

.github/workflows/ci.yml

@@ -240,6 +240,8 @@ jobs:
         with:
           toolchain: stable
           components: clippy
+      - name: Install protoc
+        run: sudo apt-get update && sudo apt-get install -y protobuf-compiler
       - name: Run cargo clippy
         run: cargo clippy
 
@@ -253,6 +255,8 @@ jobs:
         with:
           toolchain: stable
           components: rustfmt
+      - name: Install protoc
+        run: sudo apt-get update && sudo apt-get install -y protobuf-compiler
       - name: Run cargo test
         run: cargo test
 

.oxlintrc.json

@@ -1,6 +1,6 @@
 {
   "$schema": "./node_modules/oxlint/configuration_schema.json",
-  "ignorePatterns": ["__isograph", "vite-demo"],
+  "ignorePatterns": ["__isograph", "vite-demo", "sqlite-demo"],
   "plugins": ["typescript", "import"],
   "env": { "node": true, "browser": true },
   "rules": {