F3: Kimi inference pipeline + full grok cloud-surface excision

Sampler / inference (PRD F3):
- kimi_compat.rs: single adaptation point for the Kimi chat/completions
  dialect (thinking-field mapping, model_id stripping, empty-content
  tool-call message fix, stream_options.include_usage), with kimi-cli
  source citations
- Rate-limit handling reworked for Kimi/Moonshot semantics; UA kigi/{version}
- /models replaces the xAI models-v2 endpoint everywhere; idle model
  refresh carries X-Msh-* device headers only (X-XAI-Token-Auth and
  x-grok-client-mode/CLIENT_MODE_HEADER machinery deleted)

Cloud-surface excision (PRD §5, zero-egress):
- remote/ conversations lane, cli-chat-proxy-types crate, prod/ dir,
  share command, credit bar: deleted (single local session lane;
  paginate() replaces merge_and_paginate)
- Subscription/tier gate stack deleted end-to-end: AppView
  gate/tier/team/ZDR fields, app/subscription.rs watch loop,
  dispatch/billing.rs paywall + SuperGrok upsell, free-usage-exhausted
  chain, tier-restricted commands, GateInfo, RemoteSettings gate fields,
  SettingsUpdateNotification gate fields
- /privacy + coding-data-sharing setting deleted (backed by a dead xAI
  RPC; Kigi is zero-egress — nothing to share or retain remotely)

Auth UX correctness (user-reported):
- Device-flow fixtures now mirror the live Kimi payload shape
  (https://www.kimi.com/code/authorize_device?user_code=..., verified
  against auth.kimi.com); the fabricated auth.kimi.com/device?code=...
  URLs are gone
- open_browser_detached is a no-op under cfg(test): unit tests drove
  wiremock fixture URLs into the real browser (root cause of the
  "garbage mock link" ABCD-1234 tabs)
- Welcome/pager-minimal rebrand: Grok Build -> Kigi, grok.com ->
  kimi.com, "Sign in to Grok" -> "Sign in to Kimi"

Cargo.toml

@@ -75,7 +75,6 @@ members = [
     "crates/common/kigi-tool-runtime",
     "crates/common/kigi-tool-types",
     "crates/common/kigi-tracing",
-    "prod/mc/cli-chat-proxy-types",
     "third_party/dagre_rust",
     "third_party/graphlib_rust",
     "third_party/mermaid-to-svg",
@@ -337,17 +336,6 @@ strip = false
 debug = 1
 split-debuginfo = "off"
 
-# Production profile for latency-sensitive x-product services (VF, home-mixer).
-# Thin LTO gives ~90% of full LTO benefit at significantly faster link time.
-# Keeps symbols + line tables for prod debuggability (perf, flamegraph, stack traces).
-[profile.x-prod]
-inherits = "release"
-lto = "thin"
-strip = false
-codegen-units = 1
-debug = "line-tables-only"
-panic = "unwind"
-
 # Desktop release profile. Functionally identical to release-dist — kept as a
 # named alias so the desktop workflow can reference it without coupling to the
 # CLI pipeline's profile name. Alpha and stable share a single release-dist
@@ -365,7 +353,9 @@ codegen-units = 128
 debug = "line-tables-only"
 opt-level = 0
 lto = false
-incremental = true
+# Incremental caches balloon to tens of GB across this workspace's 60+ crates
+# under iterative full-workspace builds; rebuild cost is the cheaper trade.
+incremental = false
 
 [profile.bench]
 debug = true