Add uv as a prerequisite

[josemontesp]

Description

Updated /samples/client/angular/README.md to mention that uv is a prerequisite.

Without uv installed, running $ npm run demo:restaurant on Mac fails:

$ npm run demo:restaurant
> angular-a2ui@0.0.0 demo:restaurant
> npm run build:web_core && concurrently -k -n "AGENT,WEB" -c "magenta,blue" "npm run serve:agent:restaurant" "npm start -- restaurant"


> angular-a2ui@0.0.0 build:web_core
> cd ../../../renderers/web_core && npm install && npm run build


up to date, audited 37 packages in 429ms

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found 0 vulnerabilities

> @a2ui/web_core@0.8.2 build
> wireit

✅ Ran 0 scripts and skipped 2 in 0.1s.
[AGENT] 
[AGENT] > angular-a2ui@0.0.0 serve:agent:restaurant
[AGENT] > cd ../../agent/adk/restaurant_finder && uv run .
[AGENT] 
[WEB] 
[WEB] > angular-a2ui@0.0.0 start
[WEB] > ng serve restaurant
[WEB] 
[AGENT] sh: uv: command not found
[AGENT] npm run serve:agent:restaurant exited with code 127
--> Sending SIGTERM to other processes..
[WEB] npm start -- restaurant exited with code SIGTERM

Pre-launch Checklist

• I signed the CLA.
• I read the Contributors Guide.
• I read the Style Guide.
• I have added updates to the CHANGELOG. N/A
• I updated/added relevant documentation. N/A
• My code changes (if any) have tests. N/A

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[gemini-code-assist]

Code Review

This pull request adds uv as a prerequisite to the Angular client samples' README file and includes several formatting improvements. I've suggested a couple of fixes to the list formatting in the README to ensure they are rendered correctly as sub-lists. Additionally, the pull request description is incomplete. According to the repository's style guide (lines 18-20), the pre-review checklist should be completed. Please update the description to reflect the work done and fill out the checklist.