docs: syntax highlighting tags in SHOWCASE.md

SHOWCASE.md

@@ -6,7 +6,7 @@ Infer the **unwritten convention** from existing examples. Given N example
 sequences, produce a ~100-char grammar that captures the structural
 pattern — in far fewer tokens than the originals.
 
-```
+```text
 a.b       → a then b (concatenation)
 (a+b)     → a or b (disjunction)
 r?        → optional (zero or one)
@@ -20,7 +20,7 @@ r+?       → zero or more
 for the module ordering in `tasks/main.yml`. Our grammar is its first
 explicit description:
 
-```
+```text
 Grammar: fail?.(include_vars+set_fact+package+file+template+service+...)+.
          include+?.(npm+pip)+?.lineinfile?
 ```
@@ -39,7 +39,7 @@ No guessing.
 Set `min_coverage=0.8` to find the tight grammar for the majority while
 flagging outlier roles with unusual module usage:
 
-```
+```text
 Core CRX (80% coverage, 3 outliers):
   fail?.(include_vars+set_fact+package+file+template+service+...)+
 
@@ -57,7 +57,7 @@ from the mainstream install → configure → enable pattern.
 
 6 different `values.yaml` files rendered through the same chart:
 
-```
+```text
 Best: iDRegEx | MDL 1433
 Grammar: ServiceAccount.ClusterRole.ClusterRoleBinding.Service.Deployment
 ```
@@ -71,7 +71,7 @@ vocabulary (19 kinds). Which one an agent uses depends on the task:
 
 Lint jobs from prometheus, goreleaser, cosign, sigstore:
 
-```
+```text
 Best: CRX | MDL 13.6
 Grammar: actions/checkout.(actions/setup-go+run:echo+run:sudo)+.
          golangci/golangci-lint-action?.megalinter?