docs: refresh dash README to house style

[ashpreetbedi]

Summary

Docs-only refresh of README.md to the house style (tagline → intro → How it works → Quick start → Interfaces → Deploy → Configuration → Evals → Links). Every command was verified against the current code (compose.yaml, scripts/, app/main.py, evals/main.py, example.env, railway.json). No code changes.

Changes

• Restructured to the house-style section order; cut the long five-layer engineering essay into a short "How it works" (agents, context layers, learning loop, schema guardrails) — all claims verified against dash/team.py, dash/agents/, db/session.py, dash/tools/build.py.
• Removed the "Institutional Knowledge — MCP (optional)" context layer row: nothing in the codebase wires MCP, and agno's built-in MCP server supersedes manual MCP setup. Context table is now five verified layers.
• Removed the unused PORT env var from the configuration table — nothing reads it; port 8000 is hardcoded in compose.yaml and railway.json startCommand.
• Deploy section now explicitly notes the single-replica scheduler constraint (numReplicas: 1 in railway.json) and that production boot requires JWT_VERIFICATION_KEY (authorization is enabled when RUNTIME_ENV=prd, the default; app crash-loops until the key is set).
• Evals section now documents the actual CLI surface from evals/__main__.py: --category, --verbose, plus the smoke and improve subcommands (previously undocumented).
• Documented the knowledge-refresh daily scheduled task (04:00 UTC) registered in app/main.py.
• Kept verified Railway flow (railway_up.sh → JWT key → railway_env.sh → railway_redeploy.sh, railway ssh --service dash for in-network data scripts), Slack pointer to docs/SLACK_CONNECT.md, and quick-start commands unchanged in substance.
• CONTRIBUTING.md and docs/*.md checked — accurate as-is, no changes needed.

Non-doc issues spotted (NOT changed — for reviewer)

• pyproject.toml lists mcp as a dependency but nothing in the codebase imports it; likely removable (belongs in the dependency-bump PR, not this docs PR).
• compose.yaml/railway.json hardcode port 8000 while old README implied a PORT env var; if configurable port is desired, that's a code change.

Orthogonal to the open chore/update-* bump PR; contains no version or code changes.

🤖 Generated with Claude Code

[ashpreetbedi]

🤖 Automated re-review

• [medium] README.md:66 — README says python -m app.main starts the AgentOS server on :8000, but it binds to 7777. app/main.py:108-112 calls agent_os.serve(app="app.main:app", reload=...) with no port; agno 2.5.14 AgentOS.serve defaults to port=7777, overridable only via AGENT_OS_PORT, which is not set anywhere in the repo. The --port 8000 exists only in compose.yaml and railway.json uvicorn start commands, which do not run python -m app.main. This PR newly introduced the wrong :8000 comment. A user following "Local development (without the API container)" who opens localhost:8000/docs gets connection refused — the server is on :7777.