fix: update Go toolchain to 1.26.5

[fsargent]

Description

Update the Go toolchain from 1.26.4 to 1.26.5.

Go 1.26.5 fixes the std/os symlink vulnerability reported as SNYK-GOLANG-STDOS-17905377.

Checklist

• Tests added and all succeed. N/A because this change only updates the Go toolchain. Existing tests pass.
• Linted
• README.md updated, if user-facing. N/A because this change does not affect users.

🚨After having merged, please update the snyk-ls and CLI go.mod to pull in latest client.

[fsargent]

• fix: update Go toolchain to 1.26.5 #175 👈 (View in Graphite)
• main

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[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues
✅	Code Security	0	0	0	0	0 issues
✅	Secrets	0	0	0	0	0 issues

💻 Catch issues earlier using the plugins for VS Code, JetBrains IDEs, Visual Studio, and Eclipse.

[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues
✅	Code Security	0	0	0	0	0 issues

💻 Catch issues earlier using the plugins for VS Code, JetBrains IDEs, Visual Studio, and Eclipse.

[snyk-pr-review-bot]

PR Reviewer Guide 🔍

🧪 No relevant tests

🔒 No security concerns identified

⚡ No major issues detected

📚 Repository Context Analyzed This review considered 4 relevant code sections from 4 files (average relevance: 0.71) CONTRIBUTING.md (lines 1-203) README.md (lines 1-152) internal/analysis/fake.json (lines 7-11) internal/deepcode/pacts/code-client-go-snykcodeapi.json (lines 319-336)

🤖 Repository instructions applied (from AGENTS.md)