chore: rename quicproquo → quicprochat in docs, Docker, CI, and packaging

Rename all project references from quicproquo/qpq to quicprochat/qpc
across documentation, Docker configuration, CI workflows, packaging
scripts, operational configs, and build tooling.

- Docker: crate paths, binary names, user/group, data dirs, env vars
- CI: workflow crate references, binary names, artifact names
- Docs: all markdown files under docs/, SDK READMEs, book.toml
- Packaging: OpenWrt Makefile, init script, UCI config (file renames)
- Scripts: justfile, dev-shell, screenshot, cross-compile, ai_team
- Operations: Prometheus config, alert rules, Grafana dashboard
- Config: .env.example (QPQ_* → QPC_*), CODEOWNERS paths
- Top-level: README, CONTRIBUTING, ROADMAP, CLAUDE.md

sdks/ruby/quicprochat.gemspec

@@ -1,12 +1,12 @@
 Gem::Specification.new do |s|
-  s.name        = "quicproquo"
+  s.name        = "quicprochat"
   s.version     = "0.1.0"
-  s.summary     = "Ruby SDK for quicproquo E2E encrypted messenger"
-  s.description = "Ruby FFI bindings to libquicproquo_ffi for the quicproquo " \
+  s.summary     = "Ruby SDK for quicprochat E2E encrypted messenger"
+  s.description = "Ruby FFI bindings to libquicprochat_ffi for the quicprochat " \
                   "end-to-end encrypted messaging system."
-  s.authors     = ["quicproquo contributors"]
+  s.authors     = ["quicprochat contributors"]
   s.license     = "MIT"
-  s.homepage    = "https://github.com/nicholasgasior/quicproquo"
+  s.homepage    = "https://github.com/nicholasgasior/quicprochat"
 
   s.required_ruby_version = ">= 3.1"