feat(labeler): enhance Linux support detection logic

* Added handling for dedicated server tool AppIDs in Steam API checks.
* Introduced a checkbox confirmation mechanism for Linux support, improving evidence assessment.
* Updated verdict messaging to clarify Linux support status based on new checks.

Co-authored-by: Copilot <copilot@github.com>

Author: dgibbs64

.github/workflows/labeler.yml

@@ -808,7 +808,10 @@ jobs:
               const hasLinuxEvidence = linuxEvidencePatterns.some((re) => re.test(supportEvidenceText));
 
               // Steam API check: platforms.linux for the given AppID.
-              let steamLinuxSupport = null;
+              // Note: dedicated server tool AppIDs (e.g. 403240, 869800) return success:false
+              // because they have no store page. This is NOT evidence of no Linux support.
+              let steamLinuxSupport = null; // true=yes, false=no, null=unknown/inconclusive
+              let steamAppIsServerTool = false; // success:false from store API
               if (steamAppId) {
                 try {
                   const steamRes = await fetch(
@@ -821,6 +824,10 @@ jobs:
                     if (appData?.success && appData?.data?.platforms) {
                       steamLinuxSupport = appData.data.platforms.linux === true;
                       console.log(`Steam AppID ${steamAppId} linux=${steamLinuxSupport}`);
+                    } else if (appData?.success === false) {
+                      // Dedicated server tool AppIDs have no store page — inconclusive, not negative.
+                      steamAppIsServerTool = true;
+                      console.log(`Steam AppID ${steamAppId} has no store page (likely a server-tool AppID)`);
                     }
                   }
                 } catch (err) {
@@ -874,6 +881,11 @@ jobs:
                 }
               }
 
+              // Linux checkbox — used as soft positive evidence only when no negative signals exist.
+              // We don't fully trust it (users tick it without checking) but it matters when
+              // Steam API is inconclusive (server-tool AppID) and no negative patterns were found.
+              const linuxCheckboxChecked = /\[x\]/i.test(extractSection('Linux support'));
+
               // Determine verdict: confirmed = deterministic evidence; suggested = AI advisory.
               const noLinuxFromDeterministicText =
                 deterministicWindowsOnly ||
@@ -890,6 +902,14 @@ jobs:
               const linuxYesFromAi =
                 aiLinuxAssessment?.linux_support === 'yes' &&
                 (aiLinuxAssessment?.confidence === 'high' || aiLinuxAssessment?.confidence === 'medium');
+              // Soft positive: checkbox checked with no negative signals and no definitive Steam yes.
+              // Covers the common case of server-tool AppIDs where Steam API is inconclusive.
+              const likelySupportedByCheckbox =
+                linuxCheckboxChecked &&
+                !confirmedNoLinux &&
+                !suggestsNoLinux &&
+                !confirmedLinuxFromSteam &&
+                !linuxYesFromAi;
 
               const NO_LINUX_LABEL = 'status: no linux support';
               const LINUX_MARKER = '<!-- linux-support-check -->';
@@ -927,26 +947,40 @@ jobs:
               if (isSteamNo) reasons.push('request is marked as non-Steam, so Steam platform checks were intentionally skipped');
               if (noLinuxFromSteam) reasons.push(`Steam API reports no Linux platform support for AppID ${steamAppId}`);
               if (confirmedLinuxFromSteam) reasons.push(`Steam API reports Linux platform support for AppID ${steamAppId}`);
+              if (steamAppIsServerTool) reasons.push(`AppID ${steamAppId} has no Steam store page (common for dedicated server tools) — Steam platform check inconclusive`);
               if (noLinuxFromAi && aiLinuxAssessment?.reason) reasons.push(`AI analysis of provided documentation: ${aiLinuxAssessment.reason}`);
               if (linuxYesFromAi && aiLinuxAssessment?.reason) reasons.push(`AI analysis indicates Linux support: ${aiLinuxAssessment.reason}`);
+              if (likelySupportedByCheckbox) reasons.push('requester confirmed Linux support via the form checkbox; no contradicting evidence found');
 
               let verdictLine = 'Linux support could not be confirmed automatically from the submitted details.';
               if (confirmedNoLinux) {
                 verdictLine = 'This server request does **not** appear to have native Linux support, which is required for LinuxGSM.';
               } else if (suggestsNoLinux) {
                 verdictLine = 'This server request **may not** have native Linux support based on submitted evidence.';
               } else if (confirmedLinuxFromSteam) {
-                verdictLine = 'Steam metadata indicates this server supports Linux.';
+                verdictLine = 'Steam metadata confirms this server has Linux platform support.';
               } else if (linuxYesFromAi) {
                 verdictLine = 'Submitted documentation appears to indicate Linux server support.';
+              } else if (likelySupportedByCheckbox) {
+                verdictLine = 'Linux support is **likely** — the requester confirmed it and no contradicting evidence was found. A maintainer should verify before accepting.';
               }
 
+              const steamApiStatus = isSteamNo
+                ? 'Not applicable'
+                : steamLinuxSupport === true
+                  ? 'Linux supported'
+                  : steamLinuxSupport === false
+                    ? 'Linux not supported'
+                    : steamAppIsServerTool
+                      ? 'Inconclusive — AppID has no store page (typical for dedicated server tools)'
+                      : 'No definitive platform response';
+
               const steamBlock = isSteamNo
                 ? '**Steam:** No (non-Steam request)\n**Steam API:** Not applicable\n\n'
                 : steamAppId
                   ? `**Steam:** ${isSteamYes ? 'Yes' : 'Unspecified'}\n` +
                     `**Steam AppID:** ${steamAppId}\n` +
-                    `**Steam API:** ${steamLinuxSupport === null ? 'No definitive platform response' : steamLinuxSupport ? 'Linux supported' : 'Linux not supported'}\n` +
+                    `**Steam API:** ${steamApiStatus}\n` +
                     `**SteamDB:** ${steamDbLink}\n\n`
                   : `**Steam:** ${isSteamYes ? 'Yes' : 'Unspecified'}\n` +
                     '**Steam AppID:** Not provided in the issue form.\n' +