fix(projekt-matching): rename component input ctx -> ctx_in (Langflow reserves Component.ctx)

Langflow 1.10's Component base class defines ctx as a @property returning
the flow-level graph.context store; a DataInput named ctx is silently
shadowed at attribute access, so the edge-delivered payload never reaches
build_out(). Renamed the field in the five downstream Flow-2 wrappers;
build_flows.py edges target ctx_in.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

projekt-matching/components/pm_extract.py

@@ -15,7 +15,7 @@ class PMExtract(Component):
     display_name = "PM 2 Extract"
     description = "LLM 1: Anforderungen strukturiert extrahieren"
     inputs = [
-        DataInput(name="ctx", display_name="Context"),
+        DataInput(name="ctx_in", display_name="Context"),
         MessageTextInput(name="vllm_base", display_name="vLLM Base",
                          value="PM_VLLM_BASE", load_from_db=True,
                          advanced=True),
@@ -28,6 +28,6 @@ class PMExtract(Component):
     def build_out(self) -> Data:
         cfg = Cfg(vllm_base=self.vllm_base, vllm_model=self.vllm_model)
         ctx = stages.run_stage("extract", stages.stage_extract,
-                               dict(self.ctx.data), cfg)
+                               dict(self.ctx_in.data), cfg)
         self.status = ctx.get("status", "")
         return Data(data=ctx)