chore(deps): update couchbase, pydantic, uvicorn

[dex-the-ai]

Summary

Conservative dependency updates for python-quickstart-fastapi, opened by Hermes for Kanban task t_aacfe2c9.

This PR intentionally overlaps with (and supersedes) the following open Dependabot PRs, per the Hermes dependency-update flow which treats Dependabot PRs as context, not blockers:

• Bump uvicorn from 0.52.3 to 0.52.4 #262: uvicorn 0.52.3 -> 0.52.4
• Bump couchbase from 4.6.2 to 4.6.3 #263: couchbase 4.6.2 -> 4.6.3
• Bump pydantic from 2.13.4 to 2.13.5 #264: pydantic 2.13.4 -> 2.13.5

If this PR merges first, the Dependabot PRs above should auto-close/rebase; otherwise this PR can be closed once any one of them merges.

Updated Dependencies

Ecosystem	Dependency	Previous	Updated	Type	Notes
Python (pip)	couchbase	4.6.2	4.6.3	direct	Latest stable on PyPI; overlaps Dependabot #263
Python (pip)	pydantic	2.13.4	2.13.5	direct	Latest stable on PyPI; overlaps Dependabot #264
Python (pip)	uvicorn	0.52.3	0.52.4	direct	Latest stable on PyPI; overlaps Dependabot #262

All other direct dependencies (fastapi, httpx, pydantic-settings, pytest, python-dotenv) were already at latest stable and are unchanged.

Validation

Package manager: pip / requirements.txt (unchanged, no new tooling introduced).

python -m pip install -r requirements.txt
python -m pytest -q

• Install: passed, no dependency resolution conflicts.
• Tests: 47 passed, 9 warnings in ~21s, run against a live Couchbase Capella cluster with the travel-sample bucket (credentials sourced from local Hermes machine env, not committed; app/.env remains gitignored).
• Manual smoke check: started uvicorn app.main:app locally and confirmed /docs and /openapi.json respond 200 with the new dependency versions installed.

Reviewer Evidence (Swagger/OpenAPI UI)

Screenshot and short walkthrough video captured against the running app on the updated dependencies, uploaded to Cloudinary:

UI screenshot

Walkthrough video

Open the UI walkthrough

Risk Notes

• All three bumps are patch-level releases with no known breaking changes; test suite covers airline/airport/route/hotel routers end-to-end against a real cluster and all pass unchanged.
• No compatibility fixes were required; diff is limited to requirements.txt version pins.

Rollback

Revert this PR to restore the previous pins (couchbase==4.6.2, pydantic==2.13.4, uvicorn==0.52.3).

Links

Hermes Kanban task: t_aacfe2c9