mesh-issues: take every condition key the controller raises, a delivery's with its slash among them (hq issue 475)

The tracker's own pattern refused the slash a delivery's id carries, so no issue
could track a delivery's condition and the operator's alert kept saying no issue
tracks it. Mirror the controller's key rule instead of a pattern of our own; a
router test proves a slashed key is matched and named end to end.

modules/mesh-issues/cmd/mesh-issues/check.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"regexp"
+	"slices"
 	"strings"
 	"unicode"
 	"unicode/utf8"
@@ -219,13 +220,42 @@ const (
 var LinkKinds = []string{LinkDuplicates, LinkRelatesTo, LinkDependsOn, LinkPullRequest, LinkDecision, LinkDesign, LinkCondition, LinkDelivery}
 
 var (
-	pullRequest  = regexp.MustCompile(`^[a-z0-9][a-z0-9._-]{0,99}#[1-9][0-9]{0,6}$`)
-	decision     = regexp.MustCompile(`^[0-9]{4}$`)
-	conditionKey = regexp.MustCompile(`^[a-z0-9][a-z0-9._:=@-]{0,199}$`)
-	deliveryID   = regexp.MustCompile(`^[A-Za-z0-9][A-Za-z0-9._:-]{0,99}$`)
-	issueNumber  = regexp.MustCompile(`^[1-9][0-9]{0,8}$`)
+	pullRequest = regexp.MustCompile(`^[a-z0-9][a-z0-9._-]{0,99}#[1-9][0-9]{0,6}$`)
+	decision    = regexp.MustCompile(`^[0-9]{4}$`)
+	deliveryID  = regexp.MustCompile(`^[A-Za-z0-9][A-Za-z0-9._:-]{0,99}$`)
+	issueNumber = regexp.MustCompile(`^[1-9][0-9]{0,8}$`)
 )
 
+// The controller's rule for a condition's key, mirrored (novox/hq issue 475): mesh-controller's
+// internal/conditions/condition.go composes every key in `Key` as `<scope>.<id>.<kind>`, the id split on its dots,
+// each token made of the bus's safe characters `A-Za-z0-9_=/-` (anything else becomes `_`, an empty token `_`),
+// and `Observation.check` refuses a scope not in its `Scopes`. A delivery's id carries its repository as
+// owner/name, so its keys hold a slash: the narrower shape this replaced refused every one of them, and no issue
+// could track a delivery's condition. Mirroring the rule, rather than widening a pattern, keeps the tracker taking
+// exactly what the controller can raise.
+var (
+	conditionScopes = []string{"machine", "plan", "call", "build", "merge", "provider", "seat", "bus", "core",
+		"probe", "mesh", "delivery", "module"}
+	conditionKeyToken = regexp.MustCompile(`^[A-Za-z0-9_=/-]+$`)
+)
+
+// MostConditionKey is the longest key a link takes: the controller sets no bound, the tracker keeps a link one line.
+const MostConditionKey = 255
+
+// isConditionKey says whether k is a key the controller could raise.
+func isConditionKey(k string) bool {
+	parts := strings.Split(k, ".")
+	if len(k) > MostConditionKey || len(parts) < 3 || !slices.Contains(conditionScopes, parts[0]) {
+		return false
+	}
+	for _, p := range parts {
+		if !conditionKeyToken.MatchString(p) {
+			return false
+		}
+	}
+	return true
+}
+
 // checkTarget is a link's target, as its kind takes it, said the one way it is kept.
 func checkTarget(kind, target string) (string, error) {
 	t := strings.TrimSpace(target)
@@ -241,7 +271,8 @@ func checkTarget(kind, target string) (string, error) {
 	case LinkDesign:
 		ok, shape = designPath.MatchString(t), "a design document, such as 03-DESIGN/01-to-be/53-the-issue-tracker.md"
 	case LinkCondition:
-		ok, shape = conditionKey.MatchString(t), "a condition's key as the controller names it"
+		ok, shape = isConditionKey(t), "a condition's key as the controller names it: <scope>.<id>.<kind>, "+
+			"the scope one of "+strings.Join(conditionScopes, ", ")+", each part of letters, digits and _=/-"
 	case LinkDelivery:
 		ok, shape = deliveryID.MatchString(t), "a delivery's id as the controller names it"
 	default: