fix(tools): report a weight definition once however it is reached

findIndirectWeights follows each Sass reference from its own read site,
so a variable two rules read was reported twice at its definition. Both
readings of a non-holding keyframe now reach it too, with different caps,
so a computed weight (`$w: calc(400 + 100)`) got the same warning twice.
Deduplicate its findings by what they report, the key
findWorkspaceWeights already used for landed findings.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/nx/check-font-weights.mjs

@@ -757,6 +757,11 @@ function capOnly(term) {
     return Boolean(term.cap) && !offScale;
 }
 
+/** What a finding reports (see `describeFinding`): one key, one message. */
+function findingKey({ file, line, name, value, cap, computed }) {
+    return JSON.stringify([file, line, name, value, cap, computed]);
+}
+
 /** A string literal in code, whole: its quote and its text. */
 const STRING_LITERAL = /^\s*(['"`])([\s\S]*)\1\s*$/;
 
@@ -2364,7 +2369,13 @@ export function findIndirectWeights(scans) {
             );
         }
     }
-    return findings;
+    // A definition several references reach (two rules reading one Sass
+    // variable, or both readings of a keyframe) is reported once.
+    return [
+        ...new Map(
+            findings.map((finding) => [findingKey(finding), finding])
+        ).values(),
+    ];
 }
 
 /**
@@ -2450,13 +2461,11 @@ export function findWorkspaceWeights(sources) {
         ...scans.flatMap((scan) => scan.findings),
         ...findIndirectWeights(scans),
     ];
-    const keyOf = ({ file, line, name, value, cap, computed }) =>
-        JSON.stringify([file, line, name, value, cap, computed]);
-    const seen = new Set(all.filter((f) => !f.landed).map(keyOf));
+    const seen = new Set(all.filter((f) => !f.landed).map(findingKey));
     const findings = [];
     for (const { landed, ...finding } of all) {
         if (landed) {
-            const key = keyOf(finding);
+            const key = findingKey(finding);
             if (seen.has(key)) continue;
             seen.add(key);
         }

tools/nx/check-font-weights.test.mjs

@@ -197,6 +197,27 @@ test('follows variables a weight refers to, through chains and files', () => {
     );
 });
 
+test('reports a definition once however many references reach it', () => {
+    const mono = "'JetBrains Mono'";
+    for (const [source, expected] of [
+        ['$w: 650; .a { font-weight: $w; } .b { font-weight: $w; }', '650'],
+        [
+            '$w: calc(400 + 100); .a { font-weight: $w; } .b { font-weight: $w; }',
+            'calc(400 + 100)',
+        ],
+        [
+            `$w: calc(400 + 100); .a { font-family: ${mono}; font-weight: $w; } .b { font-weight: $w; }`,
+            'calc(400 + 100)',
+        ],
+    ]) {
+        assert.deepEqual(
+            offScale('libs/a.scss', source),
+            [`1 $w: ${expected}`],
+            source
+        );
+    }
+});
+
 test('checks Angular style bindings and literal DOM writes', () => {
     const template = [
         '<p [style.font-weight]="active() ? 650 : 400">a</p>',
@@ -4944,7 +4965,8 @@ test('follows a weight variable in either reading of a keyframe that does not ho
     const roboto = '@keyframes k { to { font-family: Roboto; } }';
     const report = (body) =>
         findOffScaleWeights('libs/s11/g.scss', body).findings.map(
-            ({ name, value, cap }) => `${name}: ${value} cap ${cap}`
+            ({ name, value, cap }) =>
+                `${name}: ${value}${cap ? ` cap ${cap}` : ''}`
         );
     for (const [source, expected] of [
         // Mono once it has run: the variable meets the cap where it is set.
@@ -4960,6 +4982,11 @@ test('follows a weight variable in either reading of a keyframe that does not ho
             `$w: 700; ${roboto} .x { animation: k 1ms; font: $w 12px/1 ${mono}; }`,
             ['$w: 700 cap 500'],
         ],
+        // A computed weight is one finding, whichever reading reaches it.
+        [
+            `$w: calc(400 + 100); ${roboto} .x { font-family: ${mono}; animation: k 1ms; font-weight: $w; }`,
+            ['$w: calc(400 + 100)'],
+        ],
         // Mono only while it runs.
         [
             `$w: 700; .x { font-family: Roboto; animation: k 1ms; font-weight: $w; } @keyframes k { to { font-family: ${mono}; } }`,