Prepare subtree filter prefixes once per discovery

docs/roadmap/remediation.md

@@ -1,6 +1,6 @@
 # Shared reporting and PromptKit adoption remediation
 
-Status: one open finding; R1–R6 complete. R1–R3 are from the architectural review of
+Status: all seven findings complete. R1–R3 are from the architectural review of
 `f83866e44a8a9066db52cbd2aa5cccde0d69a839`. R4–R7 are from the algorithmic
 audit of `f5b2d1f80c4720b762f3301c29d5050710c210d0`; R4 is a correctness
 issue and R5–R7 are efficiency opportunities for consideration.
@@ -284,6 +284,13 @@ and forwarding, not the choice of sorting or merging mechanism.
 
 ## R7 — P3: Path discovery reparses its invariant subtree prefix
 
+**Complete.** Discovery serializes and tokenizes the requested prefix once,
+and serializes each child once. Filtering now takes O(U+L) conversion/matching
+work and O(U) retained prefix storage, excluding native metadata and report work.
+Command checks cover root, escaped slash/tilde, exact paths, descendants, sibling
+prefixes, long unmatched prefixes, and historical/explicitness composition. The
+independent ckconfig and complete aligned workspace suites pass with Go 1.27.0.
+
 **Location:** [explain.go](../../integrations/ckconfig/explain.go),
 runConfigExplanation's discovery loop and pathWithin lines 177–194.
 
@@ -309,6 +316,10 @@ not the planned native pointer semantics or discovery algorithm.
 
 ## Applying the fixes
 
+All completion markers describe fixes in the current source. Publication and
+released dependency alignment remain separate release work. The original
+observations above retain the evidence from the audited baseline.
+
 Keep fixes and regression coverage at the CommandKit adaptation/reporting
 boundaries under the [testing policy](../policy/testing.md). These findings do
 not call for reimplementation or independent verification of upstream domain