fix(onboarding): decouple partial/indicative signals from detected — partial no longer removes a question

Fix B of the pre-#59 semantic correction. The Silent Pass had only TWO effective states though the data
carries three: a `detected` mapping (a concrete artifact) AND a `partial` mapping (an indicative signal,
e.g. a CI pipeline -> secure-development-lifecycle) both flowed through capability_ids() and were fed to
the Advisor as already-present — so a weak indication silently removed a question, exactly the Welt-1/
Welt-2 transparency we want to keep.

Now three distinct states:
  - detected   -> reduces the delta immediately (auto_detected, not asked).   [unchanged]
  - partial    -> raises assumption strength but does NOT replace the question (surfaced as `indications`,
                  the capability stays in the delta and is still asked).
  - requirement-> describes a target, never the present state (already handled by Fix A's kind split).

Changes (data + thin wiring, no new architecture):
  - SilentIntakeResult.capability_ids() returns only relationship==detected; new indicative_capability_ids()
    returns the partial ones.
  - advisor_start() gains indicative_capabilities (NOT fed into the profile) and surfaces result.indications
    = indicative ∩ required − auto_detected.
  - AdvisorResult / AdvisorResponse gain `indications` (additive, contract-safe); the service passes the
    indicative ids through.

Tests: a partial CI signal is indicative-not-detected and does NOT shrink the delta; end-to-end it appears
in `indications`, not `auto_detected`, and the gap is still asked. 28 onboarding tests pass, mypy --strict
clean on the onboarding modules, demo runs, check-loc 0. Runtime effect -> deploy + smoke.

backend-compliance/compliance/api/onboarding_routes.py

@@ -41,6 +41,7 @@ class AdvisorResponse(BaseModel):
     silent_intake_summary: str = ""
     headline: str = ""
     auto_detected: List[str] = Field(default_factory=list)
+    indications: List[str] = Field(default_factory=list)        # partial signal: raises strength, still asked
     inferred_assumptions: List[InferredAssumption] = Field(default_factory=list)
     rejected_assumptions: List[RejectedAssumption] = Field(default_factory=list)
     top_5_questions: List[AdvisorQuestion] = Field(default_factory=list)
@@ -66,6 +67,7 @@ def advisor_start_endpoint(req: OnboardingAdvisorRequest) -> AdvisorResponse:
         products=req.products, markets=req.markets, industry=req.industry or "")
     return AdvisorResponse(
         silent_intake_summary=si_summary, headline=result.headline, auto_detected=result.auto_detected,
+        indications=result.indications,
         inferred_assumptions=result.inferred_assumptions, rejected_assumptions=result.rejected_assumptions,
         top_5_questions=result.next_best_questions, capability_delta=result.capability_delta,
         top_measures=result.top_measures, evidence_requests=result.evidence_requests,