feat: add PGLite-based PostgreSQL analyzer using wazero

Add experimental support for PGLite, an embedded PostgreSQL that runs
in WebAssembly via wazero. This allows database-backed type analysis
without requiring a running PostgreSQL server.

Changes:
- Add 'pglite' experiment flag (SQLCEXPERIMENT=pglite)
- Add PGLite configuration in analyzer config (url, sha256)
- Create pglite analyzer package that uses wazero runtime
- Wire PGLite analyzer into compiler when experiment is enabled

To use PGLite analyzer, enable the experiment and configure it:

  SQLCEXPERIMENT=pglite sqlc generate

  sqlc.yaml:
    sql:
      - engine: postgresql
        analyzer:
          pglite:
            url: "file://path/to/pglite.wasm"
            sha256: "..."

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: claude

internal/compiler/engine.go

@@ -10,6 +10,7 @@ import (
 	"github.com/sqlc-dev/sqlc/internal/engine/dolphin"
 	"github.com/sqlc-dev/sqlc/internal/engine/postgresql"
 	pganalyze "github.com/sqlc-dev/sqlc/internal/engine/postgresql/analyzer"
+	"github.com/sqlc-dev/sqlc/internal/engine/postgresql/pglite"
 	"github.com/sqlc-dev/sqlc/internal/engine/sqlite"
 	sqliteanalyze "github.com/sqlc-dev/sqlc/internal/engine/sqlite/analyzer"
 	"github.com/sqlc-dev/sqlc/internal/opts"
@@ -59,7 +60,12 @@ func NewCompiler(conf config.SQL, combo config.CombinedSettings) (*Compiler, err
 		c.parser = postgresql.NewParser()
 		c.catalog = postgresql.NewCatalog()
 		c.selector = newDefaultSelector()
-		if conf.Database != nil {
+
+		// Check if PGLite analyzer is configured and experiment is enabled
+		exp := opts.ExperimentFromEnv()
+		if exp.PGLite && conf.Analyzer.PGLite != nil {
+			c.analyzer = pglite.New(*conf.Analyzer.PGLite)
+		} else if conf.Database != nil {
 			if conf.Analyzer.Database == nil || *conf.Analyzer.Database {
 				c.analyzer = analyzer.Cached(
 					pganalyze.New(c.client, *conf.Database),

internal/config/config.go

@@ -123,7 +123,13 @@ type SQL struct {
 }
 
 type Analyzer struct {
-	Database *bool `json:"database" yaml:"database"`
+	Database *bool   `json:"database" yaml:"database"`
+	PGLite   *PGLite `json:"pglite" yaml:"pglite"`
+}
+
+type PGLite struct {
+	URL    string `json:"url" yaml:"url"`
+	SHA256 string `json:"sha256" yaml:"sha256"`
 }
 
 // TODO: Figure out a better name for this