fix(providers): complete NVIDIA NIM parity with other providers

Follow-up on the native NVIDIA NIM provider salvage. The original PR wired
PROVIDER_REGISTRY + HERMES_OVERLAYS correctly but missed several touchpoints
required for full parity with other OpenAI-compatible providers (xai,
huggingface, deepseek, zai).

Gaps closed:

- hermes_cli/main.py:
  - Add 'nvidia' to the _model_flow_api_key_provider dispatch tuple so
    selecting 'NVIDIA NIM' in `hermes model` actually runs the api-key
    provider flow (previously fell through silently).
  - Add 'nvidia' to `hermes chat --provider` argparse choices so the
    documented test command (`hermes chat --provider nvidia --model ...`)
    parses successfully.

- hermes_cli/config.py: Register NVIDIA_API_KEY and NVIDIA_BASE_URL in
  OPTIONAL_ENV_VARS so setup wizard can prompt for them and they're
  auto-added to the subprocess env blocklist.

- hermes_cli/doctor.py: Add NVIDIA NIM row to `_apikey_providers` so
  `hermes doctor` probes https://integrate.api.nvidia.com/v1/models.

- hermes_cli/dump.py: Add NVIDIA_API_KEY → 'nvidia' mapping for
  `hermes dump` credential masking.

- tests/tools/test_local_env_blocklist.py: Extend registry_vars fixture
  with NVIDIA_API_KEY to verify it's blocked from leaking into subprocesses.

- agent/model_metadata.py: Add 'nemotron' → 131072 context-length entry
  so all Nemotron variants get 128K context via substring match (rather
  than falling back to MINIMUM_CONTEXT_LENGTH).

- hermes_cli/models.py: Fix hallucinated model ID
  'nvidia/nemotron-3-nano-8b-a4b' → 'nvidia/nemotron-3-nano-30b-a3b'
  (verified against live integrate.api.nvidia.com/v1/models catalog).
  Expand curated list from 5 to 9 agentic models mapping to OpenRouter
  defaults per provider-guide convention: add qwen3.5-397b-a17b,
  deepseek-v3.2, llama-3.3-nemotron-super-49b-v1.5, gpt-oss-120b.

- cli-config.yaml.example: Document 'nvidia' provider option.

- scripts/release.py: Map asurla@nvidia.com → anniesurla in AUTHOR_MAP
  for CI attribution.

E2E verified: `hermes chat --provider nvidia ...` now reaches NVIDIA's
endpoint (returns 401 with bogus key instead of argparse error);
`hermes doctor` detects NVIDIA NIM when NVIDIA_API_KEY is set.

hermes_cli/models.py

@@ -156,11 +156,18 @@ _PROVIDER_MODELS: dict[str, list[str]] = {
         "grok-4-1-fast-reasoning",
     ],
     "nvidia": [
+        # NVIDIA flagship reasoning models
         "nvidia/nemotron-3-super-120b-a12b",
-        "nvidia/nemotron-3-nano-8b-a4b",
-        "z-ai/glm5",
+        "nvidia/nemotron-3-nano-30b-a3b",
+        "nvidia/llama-3.3-nemotron-super-49b-v1.5",
+        # Third-party agentic models hosted on build.nvidia.com
+        # (map to OpenRouter defaults — users get familiar picks on NIM)
+        "qwen/qwen3.5-397b-a17b",
+        "deepseek-ai/deepseek-v3.2",
         "moonshotai/kimi-k2.5",
         "minimaxai/minimax-m2.5",
+        "z-ai/glm5",
+        "openai/gpt-oss-120b",
     ],
     "kimi-coding": [
         "kimi-k2.5",
@@ -543,6 +550,7 @@ CANONICAL_PROVIDERS: list[ProviderEntry] = [
     ProviderEntry("anthropic",      "Anthropic",                "Anthropic (Claude models — API key or Claude Code)"),
     ProviderEntry("openai-codex",   "OpenAI Codex",             "OpenAI Codex"),
     ProviderEntry("xiaomi",         "Xiaomi MiMo",              "Xiaomi MiMo (MiMo-V2 models — pro, omni, flash)"),
+    ProviderEntry("nvidia",         "NVIDIA NIM",               "NVIDIA NIM (Nemotron models — build.nvidia.com or local NIM)"),
     ProviderEntry("qwen-oauth",     "Qwen OAuth (Portal)",      "Qwen OAuth (reuses local Qwen CLI login)"),
     ProviderEntry("copilot",        "GitHub Copilot",           "GitHub Copilot (uses GITHUB_TOKEN or gh auth token)"),
     ProviderEntry("copilot-acp",    "GitHub Copilot ACP",       "GitHub Copilot ACP (spawns `copilot --acp --stdio`)"),
@@ -551,7 +559,6 @@ CANONICAL_PROVIDERS: list[ProviderEntry] = [
     ProviderEntry("google-gemini-cli", "Google Gemini (OAuth)",   "Google Gemini via OAuth + Code Assist (free tier supported; no API key needed)"),
     ProviderEntry("deepseek",       "DeepSeek",                 "DeepSeek (DeepSeek-V3, R1, coder — direct API)"),
     ProviderEntry("xai",            "xAI",                      "xAI (Grok models — direct API)"),
-    ProviderEntry("nvidia",         "NVIDIA NIM",               "NVIDIA NIM (Nemotron models — build.nvidia.com or local NIM)"),
     ProviderEntry("zai",            "Z.AI / GLM",               "Z.AI / GLM (Zhipu AI direct API)"),
     ProviderEntry("kimi-coding",    "Kimi / Kimi Coding Plan",  "Kimi Coding Plan (api.kimi.com) & Moonshot API"),
     ProviderEntry("kimi-coding-cn", "Kimi / Moonshot (China)",  "Kimi / Moonshot China (Moonshot CN direct API)"),