[plugin-discovery] move logic to a package

[spalger]

Part of #94034

This PR moved the plugin discovery logic to a new package so that we can import it in @kbn/pm, which copies all imported sources into the packages/kbn-pm/dist/index.js file, so isolating the logic in a package is necessary to prevent constant unnecessary rebuilds of this dist file.

[elasticmachine]

Pinging @elastic/kibana-operations (Team:Operations)

[mistic]

LGTM

[kibana-ci]

💚 Build Succeeded

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• Commit: 33d4fdc
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Metrics [docs]

Public APIs missing comments

Total count of every public API that lacks a comment. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats comments for more detailed information.

id	before	after	diff
@kbn/dev-utils	207	199	-8
@kbn/plugin-discovery	-	27	+27
total			+19

Unknown metric groups

API count

id	before	after	diff
@kbn/dev-utils	286	277	-9
@kbn/plugin-discovery	-	28	+28
total			+19

ESLint disabled in files

id	before	after	diff
apm	15	14	-1
osquery	5	4	-1
securitySolution	69	68	-1
uptime	7	6	-1
total			-4

ESLint disabled line counts

id	before	after	diff
apm	88	85	-3
enterpriseSearch	9	7	-2
fleet	47	46	-1
osquery	122	119	-3
uptime	49	43	-6
total			-15

References to deprecated APIs

id	before	after	diff
canvas	70	64	-6
dashboard	78	72	-6
data	475	465	-10
dataEnhanced	55	49	-6
discover	26	20	-6
fleet	20	19	-1
lens	18	14	-4
management	2	1	-1
maps	456	330	-126
monitoring	40	28	-12
upgradeAssistant	12	7	-5
visDefaultEditor	205	155	-50
visTypeVega	4	3	-1
visualizations	17	13	-4
total			-238

Total ESLint disabled count

id	before	after	diff
apm	103	99	-4
enterpriseSearch	9	7	-2
fleet	55	54	-1
osquery	127	123	-4
securitySolution	509	508	-1
uptime	56	49	-7
total			-19

History

• 💔 Build #34298 failed 233f300
• 💚 Build #34242 succeeded 58763b8
• 💔 Build #34221 failed 662e095
• 💔 Build #34217 failed a90aa3b

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[kibanamachine]

💔 All backports failed

Status	Branch	Result
❌	8.1	Backport failed because of merge conflicts

Manual backport

To create the backport manually run:

node scripts/backport --pr 128684

Questions ?

Please refer to the Backport tool documentation