Split remaining over-limit Python files by responsibility #113

Summary

Split the remaining 12 Python files above 500 physical lines by responsibility, pairing implementation changes with their related tests. Measured counts and proposed boundaries are in docs/investigations/file-length-limit.md at develop commit 902c759.

Scope

• nitrostack/widgets/route_templates.py (870): separate generic, pizza, and flight/order templates; keep a small route dispatcher.

• nitrostack/transports/http.py (797): separate middleware and HTTP assembly helpers.

• nitrostack/widgets/views.py (569): separate route/view dispatch from response and preview handling.

• nitrostack/auth/oauth.py (516): separate OAuth types and token/client/cache operations only along stable dependency boundaries.

• nitrostack/cli/pack.py (507): separate file selection/ignore rules from wheel/vendor assembly.

• tests/test_cli.py (1,568): split lifecycle/ports, generation, packaging/upgrades/validation, and registration.

• tests/test_oauth.py (1,011): split guard/PKCE, metadata/discovery, and introspection/JWKS/cache.

• tests/test_transports.py (732): split HTTP/session lifecycle, protocol/header behavior, and dual transport/progress.

• tests/test_widgets.py (629): split route rendering, resource registration, metadata/host integration, and output assertions.

• tests/test_tasks.py (574): split lifecycle/progress, authorization/cancellation, and store/eviction where boundaries are cohesive.

• tests/test_secret_value.py (515): split construction/serialization, redaction/errors, and integration/security cases.

• examples/flight_booking_server.py (582): separate example-local domain code, MCP definitions, and startup/configuration.

• Keep each resulting hand-maintained Python module at or below 500 physical lines. Move static HTML/JavaScript into non-Python assets where appropriate; document a specific exception if a cohesive module cannot meet the limit.

• Preserve existing imports with facade re-exports where callers may rely on them. Preserve rendered widget output and example run instructions.

• Avoid test-module cross-imports and line-count-only reshuffling.

Acceptance criteria

• Every listed over-limit Python file is split along cohesive responsibilities and its resulting Python modules are at or below 500 physical lines, with any exception documented and justified.
• Focused tests cover preserved imports, widget output, transport behavior, and example startup as applicable.
• No unrelated behavior changes or unnecessary import cycles are introduced.

Wait for PR #37 to merge before splitting transports/http.py. Refresh open PR changed-file lists and remeasure from develop before assigning work.

Out of scope: unrelated behavior changes and broad cleanup.