refactor(lint): retrofit vale-run to the ADR-0020 context contract

Description 654 -> 294 chars, Gotchas 36% -> 19%. Body 698 -> 642 words:
up from the first pass, because a clean-context audit found four defects
whose fixes are net-additive text.

The suppression-markup warning covered only one of the two paths that
write it -- the list is case-based, so a recurring false positive goes
straight to step 3 and never read step 2's warning. Hoisted above both.

The CI-failure trigger, which the description advertises, had no path to
the file holding its answer: the negative diagnosis 'if the alerts are
warnings, Vale is not what failed the build' survived only in
troubleshooting.md, which no CI-entered invocation loads. An agent would
confidently prescribe --no-exit for a failure Vale never caused.

The description had lost every prose-domain word -- no 'prose', no
'linter' -- while vale-config kept all of them, so 'check prose style'
routed to the wrong skill of the pair.

Accepts two soft SUGGESTIONs rather than dropping restored content;
neither fails the gate.

Refs #99

plugins/lint/skills/vale-run/references/troubleshooting.md

@@ -5,6 +5,13 @@ source_keys:
 
 # Vale troubleshooting reference
 
+## Why a rule isn't applying
+
+`vale ls-config` prints the fully-resolved, currently active configuration as JSON. Check that
+before rereading `.vale.ini` — what is written in the config file is not necessarily what is
+active, and the resolved output is the fastest way to see which styles and rules a run actually
+loaded.
+
 ## Inline suppression syntax by format
 
 Markdown uses HTML comments — the MDX `{/* */}` form does not suppress anything in a plain `.md` file: