PMM-12575 change api for agents

[BupycHuk]

PMM-12575

Link to the Feature Build: SUBMODULES-0

If this PR adds or removes or alters one or more API endpoints, please review and add or update the relevant API documents as well:

• API Docs updated

If this PR is related to some other PRs in this or other repositories, please provide links to those PRs:

• Links to related pull requests (optional).

[codecov]

Codecov Report

Attention: Patch coverage is 74.00235% with 443 lines in your changes missing coverage. Please review.

Project coverage is 45.35%. Comparing base (3bce330) to head (13b3f94).
Report is 6 commits behind head on v3.

Files with missing lines	Patch %	Lines
...mmands/inventory/change_agent_postgres_exporter.go	69.23%	30 Missing and 10 partials ⚠️
.../inventory/change_agent_qan_mysql_slowlog_agent.go	68.50%	30 Missing and 10 partials ⚠️
...commands/inventory/change_agent_valkey_exporter.go	68.50%	30 Missing and 10 partials ⚠️
...commands/inventory/change_agent_mysqld_exporter.go	70.99%	27 Missing and 11 partials ⚠️
...ventory/change_agent_qan_mysql_perfschema_agent.go	69.91%	28 Missing and 9 partials ⚠️
.../change_agent_qan_postgresql_pgstatements_agent.go	68.10%	28 Missing and 9 partials ⚠️
...change_agent_qan_postgresql_pgstatmonitor_agent.go	69.91%	28 Missing and 9 partials ⚠️
...ommands/inventory/change_agent_mongodb_exporter.go	78.32%	23 Missing and 8 partials ⚠️
...ventory/change_agent_qan_mongodb_profiler_agent.go	77.47%	19 Missing and 6 partials ⚠️
.../commands/inventory/add_agent_postgres_exporter.go	0.00%	13 Missing ⚠️
... and 37 more

Additional details and impacted files

@@            Coverage Diff             @@
##               v3    #4066      +/-   ##
==========================================
+ Coverage   44.16%   45.35%   +1.18%     
==========================================
  Files         369      386      +17     
  Lines       45306    47390    +2084     
==========================================
+ Hits        20009    21492    +1483     
- Misses      23610    24136     +526     
- Partials     1687     1762      +75     

Flag	Coverage Δ
admin	32.97% <74.00%> (+15.68%)	⬆️
agent	52.73% <ø> (ø)
managed	45.03% <ø> (+0.07%)	⬆️
vmproxy	73.45% <ø> (ø)

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[Copilot]

Pull Request Overview

Adjust custom labels handling across commands, introduce a new PostgreSQL exporter connection limit flag, and enhance template utilities.

• Refactored ParseCustomLabels to accept and return pointers, updating all command usages.
• Added MaxExporterConnections flag to AddAgentPostgresExporterCommand.
• Extended base.go with FormatLogLevel and FormatCustomLabels template functions (added sort import).

Reviewed Changes

Copilot reviewed 104 out of 104 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
admin/commands/inventory/add_service_external.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_node_remote_rds.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_node_remote.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_node_generic.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_node_container.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_rds_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_qan_postgres_pgstatmonitor_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_qan_postgres_pgstatements_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_qan_mysql_slowlog_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_qan_mysql_perfschema_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_qan_mongodb_profiler_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_proxysql_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_postgres_exporter.go	Updated ParseCustomLabels call; added new flag
admin/commands/inventory/add_agent_pmm_agent.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_node_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_mysqld_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_mongodb_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/inventory/add_agent_external_exporter.go	Updated ParseCustomLabels call to use pointer
admin/commands/base_test.go	Adapted tests for pointer-based ParseCustomLabels
admin/commands/base.go	Changed ParseCustomLabels signature; added imports and template functions

Comments suppressed due to low confidence (3)

admin/commands/base.go:27

• The new FormatCustomLabels function uses fmt.Sprintf but fmt is not imported; add "fmt" to the imports to avoid compilation errors.

import (

admin/commands/base.go:221

• The new FormatCustomLabels (and FormatLogLevel) functions lack unit tests. Consider adding tests to cover these formatting helpers to prevent regressions.

func FormatCustomLabels(labels interface{}) string {

admin/commands/base.go:161

• [nitpick] Using *map[string]string is uncommon in Go since maps are reference types. Consider returning a map[string]string and using nil to represent absence for a more idiomatic API.

func ParseCustomLabels(labels *map[string]string) *map[string]string {