feat(graph): add NestJS controller route resolver

[abhinav-phi]

What

• Adds a NestJS FrameworkResolver for decorator-defined HTTP controller routes.
• Detects NestJS through @nestjs/core or @nestjs/common dependencies.
• Recognizes @Controller() prefixes and HTTP method decorators such as @Get(), @Post(), @Put(), @Patch(), @Delete(), @Options(), @Head(), and @All().
• Emits stable route nodes and function_ref references to controller methods.
• Resolves same-file handlers only when the target is unambiguous.
• Adds a NestJS fixture, focused resolver tests, and framework-registry wiring.

Why

Closes #98.

This teaches the code graph about NestJS controller routing without changing the frozen FrameworkResolver interface or graph-core semantics.

Scope boundaries

This PR is limited to statically recognizable HTTP controller routes. Dependency-injection edges, guards, pipes, interceptors, middleware, gateways, GraphQL, microservices, and runtime decorator evaluation remain out of scope.

How to test

npm run typecheck
npm test
npm run build

Focused review should verify:

• Positive and negative NestJS detection.
• Controller-prefix and method-path normalization.
• Multiple HTTP methods and parameterized paths.
• Stable route-node identity.
• Confident same-file handler resolution.
• Missing or ambiguous handlers remain unresolved.
• No graph identity, reconciliation, schema, or drift-semantics changes.