config: rename the DeepSeek flash model to deepseek-flash

DeepSeek dropped the `v4` prefix from its flash model, and the old id stays
valid only as a compatibility alias. Seed the default catalog with the current
name so a provider that omits `models` no longer offers a deprecated id, and
follow the rename in the wire fixtures and the minimal config template. An
explicit `deepseek-v4-flash` in TOML still passes through unchanged.

src/plyngent/cli/editor.py

@@ -57,7 +57,7 @@ _MINIMAL_CONFIG = """\
 # [providers.deepseek]
 # preset = "deepseek"
 # access_key_or_token = "sk-..."
-# # models default to deepseek-v4-flash and deepseek-v4-pro if omitted
+# # models default to deepseek-flash and deepseek-v4-pro if omitted
 """
 
 

src/plyngent/config/models.py

@@ -366,7 +366,7 @@ class AnthropicProvider(ProviderConfig, tag="anthropic"):
 def _default_deepseek_models() -> dict[str, ModelConfig]:
     """Current DeepSeek text catalog when TOML omits ``models``."""
     return {
-        "deepseek-v4-flash": ModelConfig(text=True),
+        "deepseek-flash": ModelConfig(text=True),
         "deepseek-v4-pro": ModelConfig(text=True),
     }
 

src/plyngent/lmproto/deepseek/anthropic/client.py

@@ -17,8 +17,8 @@ class DeepseekAnthropicClient(AnthropicClient):
     (see https://api-docs.deepseek.com/guides/anthropic_api). ``x-api-key`` is fully
     supported; ``anthropic-version`` / ``anthropic-beta`` headers are ignored by the
     server but harmless. Model ids map server-side: ``claude-opus*`` → ``deepseek-v4-pro``,
-    ``claude-haiku*`` / ``claude-sonnet*`` → ``deepseek-v4-flash``, unknown names →
-    ``deepseek-v4-flash``; real DeepSeek ids pass through as-is.
+    ``claude-haiku*`` / ``claude-sonnet*`` → ``deepseek-flash``, unknown names →
+    ``deepseek-flash``; real DeepSeek ids pass through as-is.
 
     ``GET /models`` is not documented on the ``/anthropic`` base, so ``models()``
     returns an empty list and model selection stays config-driven.