refactor(compiler): split semantic IR source maps and target plans

[cssbruno]

Summary

• Split standalone Go endpoint source fidelity out of the semantic IR by replacing Program.GoEndpoints with Program.SourceMap entries keyed by stable EndpointID.
• Keep normalized standalone Go endpoints in Program.Endpoints so validation, binding lookup, route checks, and generated-output planners consume semantic records instead of raw declaration records.
• Carry stable typed IDs for pages, components, layouts, routes, and endpoints through IR assembly, invariant checks, backend binding lookup, and appgen endpoint planning.
• Document the semantic IR/source-map boundary and the target-plan boundary for buildgen/appgen consumers.

Issue Closure

Closes #668
Related: #664
Related: #667

Verification

• I ran the relevant tests, lint, and build commands.
• I ran scripts/test-go-modules.sh when Go code or compiler behavior changed.
• I ran go build ./cmd/gowdk when CLI, compiler, runtime, addon, or release behavior changed.
• I ran node --check editors/vscode/extension.js when editor files changed.
• I updated docs for behavior, setup, or architecture changes.
• I added or updated tests for changed behavior.
• I considered security-sensitive surfaces such as auth, CSRF, redirects, request-time handlers, logs, diagnostics, embedded assets, editor commands, WASM, contracts, and realtime behavior.

Commands run:

• go test ./internal/gwdkir ./internal/gwdkanalysis
• go test ./internal/compiler
• go test ./internal/appgen
• go test ./internal/buildgen ./internal/lsp
• go test ./internal/diagnostics ./internal/diagnosticfix
• go build ./cmd/gowdk
• go run ./cmd/gowdk inspect ir examples/pages/home.page.gwdk
• scripts/check-docs-links.sh
• scripts/check-docs-style.sh
• scripts/test-go-modules.sh

LLM Assistance

• LLM session summary: Codex implemented the semantic IR/source-map split for standalone Go endpoints, carried typed semantic IDs through IR and generated-output planning boundaries, updated invariants/tests/docs, and verified the full Go module gate.
• Human-reviewed assumptions: Split gwdkir.Program into semantic IR and target-specific plans #668 is fully resolved by this PR because gwdkir.Program now separates normalized semantic endpoint records from diagnostic source-map records and generated-output consumers carry semantic IDs into target-specific plans. Make typed IR fields the only semantic source of truth #664 and Introduce phase-typed validated program and application plan boundaries #667 remain related follow-up issues because their broader typed-only and phase-boundary acceptance criteria are not fully closed here.
• Follow-up work: Continue Make typed IR fields the only semantic source of truth #664 and Introduce phase-typed validated program and application plan boundaries #667 in separate PRs without reopening the Program.GoEndpoints semantic/raw declaration coupling.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: af0b3a5623

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Avoid treating duplicate endpoints as IR invariants

When a user declares the same endpoint block twice with the same page/name/method/path (for example two Save actions inheriting /profile), both builder-created endpoints get the same semantic ID, so this new invariant returns an internal compiler error before validateRouteMethodConflicts/page validators can report a normal author diagnostic. Duplicate route registrations are authoring errors, not compiler invariants, so this uniqueness check should either be moved into validation or limited to cases that cannot be produced from user input.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Escape the identity separator

Because url.PathEscape leaves : unchanged while : is also the tuple separator, different semantic tuples can collapse into the same ID. For example, RouteIdentity("GET", "/foo:bar", "baz") and RouteIdentity("GET", "/foo", "bar:baz") both become GET:%2Ffoo:bar:baz; literal route segments and page IDs with colons are accepted today, so valid pages can get the same RouteID and trip the duplicate-ID invariant as an internal compiler error. Use an encoding that also escapes the separator, or switch to a length-prefixed/structured key.

Useful? React with 👍 / 👎.