(chore): bump go version 1.26.4

[manav2401]

No description provided.

[claude]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull request overview

This PR updates the repository’s Go toolchain version to 1.26.4 and aligns the Docker build images and lint configuration accordingly. It also refreshes a few golang.org/x/* indirect dependencies within the cmd/keeper submodule (likely as a result of running module maintenance under the new toolchain).

Changes:

• Bump go directive from 1.26.3 → 1.26.4 in the root module and cmd/keeper submodule.
• Update builder images in Dockerfile and Dockerfile.alltools to golang:1.26.4-alpine.
• Update cmd/keeper indirect deps/checksums (golang.org/x/crypto, golang.org/x/sys, golang.org/x/text).

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
go.mod	Bumps root module Go version to 1.26.4.
Dockerfile.alltools	Updates Go builder image tag to 1.26.4-alpine.
Dockerfile	Updates Go builder image tag to 1.26.4-alpine.
cmd/keeper/go.sum	Refreshes submodule dependency checksums (includes golang.org/x/* bumps).
cmd/keeper/go.mod	Bumps submodule Go version and updates a couple indirect deps.
.golangci.yml	Aligns golangci-lint run Go version to 1.26.4.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 53.42%. Comparing base (706b800) to head (ee6f2b3).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2258      +/-   ##
===========================================
+ Coverage    53.41%   53.42%   +0.01%     
===========================================
  Files          896      896              
  Lines       159713   159713              
===========================================
+ Hits         85314    85332      +18     
+ Misses       69071    69054      -17     
+ Partials      5328     5327       -1     

see 16 files with indirect coverage changes
see 16 files with indirect coverage changes

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