feat: provider connection details pages

[beubax]

Description

Adds dedicated provider and connection detail pages to the UI. Provider details show configuration, usage, revoke, and replace-config flows for admins, while non-admins only see their own connection usage. Connection details show stored secrets/tokens and allow logout. Dynamic detail routes were changed to static-export-safe query-param routes.

Motivation and Context

This restores missing detail pages that regressed from the UI and gives users a clean place to inspect provider setup and individual connection credentials. It also preserves static Next.js export compatibility.

How Has This Been Tested?

Tested with focused backend coverage for provider/connection detail permissions, admin config updates, and logout behavior. Also verified frontend type checking, linting, and static production build.

Commands run:
uv run pytest tests/server/test_connection_details.py tests/server/test_provider_details.py tests/auth/test_service_provider_clients.py -v
uv run ruff check src/ tests/
uv run ty check src/
uv run pre-commit run --all-files
pnpm exec tsc --noEmit
pnpm exec eslint
pnpm build

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• I have read the CONTRIBUTING document.
• All new and existing tests passed.