Compose umbrella synapse chart and demo values

[NickCrew]

Description

Create the top-level operator experience after the component charts exist. This chart should let users install a complete Synapse stack while still allowing them to install Fleet or WAF separately.

Include values examples for demo and production-shaped installs. Treat bundled dependencies as convenience profiles rather than production defaults.

Acceptance Criteria

• Migrate synapse-waf to Rust 2024 edition #1 Umbrella chart composes synapse-fleet and synapse-waf with sane default wiring between Fleet and WAF telemetry
• Cache parsed EvalContext data across body-phase and deferred WAF passes #2 Demo values can install a working non-production stack with explicit dependency choices
• Instantiate and integrate HeaderProfiler for per-endpoint header anomaly detection #3 Production values example uses externally managed PostgreSQL/Redis and does not expose admin surfaces publicly by default
• Escalate invalid-session weight non-linearly to catch faster brute-force #4 helm template output is validated for default, demo, and production-example values

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Migrated from backlog TASK-103.5 (synapse).