docs(session-replay): Add documentation for V2 trigger groups and migration feature

[inkeep]

Changes

This PR updates the Session Replay documentation to cover the new V2 trigger groups feature and migration workflow introduced in PostHog/posthog#53122.

Updates to contents/docs/session-replay/how-to-control-which-sessions-you-record.mdx:

• New "Trigger groups" section – Explains the V2 trigger groups concept where each group has its own combination of URL triggers, event triggers, feature flags, sample rate, minimum duration, and match type (ANY/ALL)
• New "Migrating from legacy trigger settings" subsection – Documents the "Create from legacy triggers" button and explains the migration workflow, including why 2 groups may be created when legacy settings use ANY match type with sampling

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Status	Details	Updated (UTC)
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Vale prose linter → found 10 errors, 15 warnings, 1 suggestions in your markdown

Full report → Copy the linter results into an LLM to batch-fix issues.

Linter being weird? Update the rules!

contents/docs/session-replay/how-to-control-which-sessions-you-record.mdx — 10 errors, 15 warnings, 1 suggestions

Line	Severity	Message	Rule
18:54	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
20:54	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
22:54	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
24:54	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
30:142	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
30:246	warning	Capitalize 'Feature Flags' for PostHog's product. Use 'feature flags' for the general industry concept.	PostHogBase.ProductNames
30:308	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
71:4	warning	'With Event trigger conditions' heading should be in sentence case, and product names should be capitalized.	PostHogBase.SentenceCase
73:7	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
85:13	warning	Capitalize 'Error Tracking' for PostHog's product. Use 'error tracking' for the general industry concept.	PostHogBase.ProductNames
107:74	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
109:23	warning	'navigations' is a possible misspelling.	PostHogBase.Spelling
111:9	warning	Capitalize 'Feature Flags' for PostHog's product. Use 'feature flags' for the general industry concept.	PostHogBase.ProductNames
132:1	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
132:13	warning	Use 'PostHog' instead of 'posthog'.	Vale.Terms
133:1	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
134:1	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
135:1	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
144:142	error	Use straight quotes and apostrophes, not curly ones.	PostHogDocs.CurlyQuotes
144:177	error	Use straight quotes and apostrophes, not curly ones.	PostHogDocs.CurlyQuotes
158:125	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
176:154	warning	Capitalize 'Feature Flags' for PostHog's product. Use 'feature flags' for the general industry concept.	PostHogBase.ProductNames
190:77	warning	Capitalize 'Feature Flags' for PostHog's product. Use 'feature flags' for the general industry concept.	PostHogBase.ProductNames
199:107	warning	Capitalize 'Feature Flags' for PostHog's product. Use 'feature flags' for the general industry concept.	PostHogBase.ProductNames
255:24	suggestion	Address the reader directly. Use 'you' instead of 'the user'.	PostHogDocs.DirectAddress
264:87	warning	'navigations' is a possible misspelling.	PostHogBase.Spelling