refactor(server): standardize server env config prefixes

[lan17]

Summary

• standardize server-owned config on canonical AGENT_CONTROL_* env vars
• remove legacy server env aliases and switch the database config to true env_prefix-based settings
• update server-facing compose, Docker, Makefile, and test docs to use the new canonical names

Verification

• uv run --package agent-control-server pytest server/tests/test_config.py server/tests/test_logging_utils.py --noconftest -q
• make lint
• make typecheck

Notes

• This PR intentionally migrates server env var names without legacy compatibility fallbacks.
• I did not run the full DB-backed make server-test suite in this environment.

[codecov]

Codecov Report

❌ Patch coverage is 97.64706% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
server/src/agent_control_server/logging_utils.py	94.73%	2 Missing ⚠️

📢 Thoughts on this report? Let us know!

[namrataghadi-galileo]

Problem

server/.env.example (line 44) documents only the split AGENT_CONTROL_DB_HOST / PORT / USER / PASSWORD / DATABASE variables, but the app also supports AGENT_CONTROL_DB_URL and the repo now uses that as the primary Docker example in docker-compose.yml (line 47).
That means someone reading .env.example can miss the simplest supported DB config even though the code clearly accepts it in config.py (line 109).

Suggestion:
Add following after line 44 in server/.env.example

# Preferred single-variable form:
AGENT_CONTROL_DB_URL=postgresql+psycopg://agent_control:agent_control@localhost:5432/agent_control

[lan17]

@namrataghadi-galileo addressed in ac5ee6b. I updated server/.env.example to document AGENT_CONTROL_DB_URL as the preferred single-variable form, with the expanded AGENT_CONTROL_DB_* settings kept below as the alternative.

[namrataghadi-galileo]

Thank you