refactor: migrate JSON from sonic to encoding/json/v2

[yusing]

Summary

Stacked on #252 (feat/go1.27).

Replace bytedance/sonic with Go 1.27 encoding/json/v2 as the JSON backend wired into strutils. Drop USE_SONIC_JSON and the SIGILL workaround.

Changes

• internal/serialization always registers encoding/json/v2 + encoding/json/jsontext on strutils (setupJSONV2())
• time.Duration keeps v1 nanosecond numbers via encoding/json.FormatDurationAsNano, so health/timeout JSON still round-trips
• Agent proxy cache keys use json/v2 instead of sonic.Marshal
• Remove USE_SONIC_JSON from .env.example, rootless env, agent compose template, install script, agent logs, and user-facing wiki

Not dropped

Gin still lists github.com/bytedance/sonic as an indirect module because gin/codec/json has a //go:build sonic file. Default gin builds do not use that codec.

Docs

Wiki and webui submodule branches:

• https://github.com/yusing/godoxy-wiki/tree/feat/json-v2
• https://github.com/yusing/godoxy-webui/tree/feat/json-v2

Summary by CodeRabbit

• Improvements

  • Standardized JSON handling for more consistent serialization and validation.
  • Removed the optional high-performance JSON backend and related configuration settings.
  • Simplified startup messaging and generated environment configuration.

• Documentation

  • Updated configuration and integration documentation to reflect current JSON behavior and serialization utilities.

• Maintenance

  • Refreshed supporting components and streamlined dependency management.

[coderabbitai]

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 2c65b3db-8c54-4bd2-a957-dee3e37213f7

📥 Commits

Reviewing files that changed from the base of the PR and between 3dd1bf9 and 340c957.

⛔ Files ignored due to path filters (1)

• internal/dnsproviders/go.sum is excluded by !**/*.sum

📒 Files selected for processing (20)

• .env.example
• agent/cmd/main.go
• agent/go.mod
• agent/pkg/agent/templates/agent.compose.yml.tmpl
• agent/pkg/handler/proxy_http.go
• go.mod
• goutils
• internal/dnsproviders/go.mod
• internal/homepage/integrations/qbittorrent/README.md
• internal/homepage/override_config_test.go
• internal/jsonstore/README.md
• internal/metrics/README.md
• internal/metrics/period/README.md
• internal/metrics/uptime/README.md
• internal/notif/webhook.go
• internal/serialization/README.md
• internal/serialization/serialization.go
• rootless.env.example
• scripts/install-agent.sh
• webui

Cache: Disabled due to Reviews > Disable Cache setting

Knowledge base: Disabled due to Reviews -> Disable Knowledge Base setting

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📝 Walkthrough

Walkthrough

The change removes optional Sonic JSON initialization and configuration. Proxy caching and webhook validation use goutils/strings. Module requirements, documentation, generated environment files, startup messages, and submodule references are updated.

Changes

Sonic JSON removal

Layer / File(s)	Summary
Serialization path and documentation internal/serialization/serialization.go, agent/pkg/handler/proxy_http.go, internal/notif/webhook.go, internal/serialization/README.md, internal/jsonstore/README.md, internal/metrics/**, internal/homepage/**	YAML-only initialization remains. Proxy cache keys use strutils.MarshalString. Webhook validation uses strutils.ValidJSONString. Documentation identifies encoding/json/v2 as the JSON implementation.
Configuration and startup cleanup agent/cmd/main.go, agent/pkg/agent/templates/agent.compose.yml.tmpl, rootless.env.example, scripts/install-agent.sh	Startup messages and generated configuration no longer include Sonic status, USE_SONIC_JSON, or SIGILL guidance.
Dependency graph and submodule updates go.mod, agent/go.mod, internal/dnsproviders/go.mod, goutils, webui	Sonic moves from direct to indirect requirements. Obsolete DNS-provider dependencies are removed. The goutils and webui submodule references are updated.

Estimated code review effort: 2 (Simple) | ~10 minutes

Poem

I’m a rabbit with a tidy JSON nest,
Sonic hopped out; the helpers do the rest.
YAML stays where it belongs,
Config tips no longer sing their songs.
Dependencies shed a few old leaves—
Clean paths grow beneath my paws and sleeves.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 25.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the primary change: replacing Sonic with encoding/json/v2 for JSON serialization.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• ✅ Committed to branch successfully - (🔄 Check to regenerate)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/json-v2

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch feat/json-v2

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_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

Note

Docstrings generation - SUCCESS
Generated docstrings and committed to branch feat/json-v2 (commit: 014add97d520a0578e6ab55a715fea532d2e0ba1)

[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