chore: make all the deprecated feature flag reclaimable (#13646)

## Docs

https://www.notion.so/chatwoot/Redeeming-a-depreciated-feature-flag-313a5f274c9280f381cdd811eab42019?source=copy_link

## Description
Marks 8 unused feature flags as deprecated: true in features.yml,
freeing their bit slots for future reuse.
Removes dead code references from JS constants, help URLs, and
enterprise billing config.

## Type of change

- [ ] Bug fix (non-breaking change which fixes an issue)

## How Has This Been Tested?

- Simulated the "claim a slot" workflow 

## Checklist:

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

config/features.yml

@@ -108,12 +108,10 @@
 - name: response_bot
   display_name: Response Bot
   enabled: false
-  premium: true
   deprecated: true
 - name: message_reply_to
   display_name: Message Reply To
   enabled: false
-  help_url: https://chwt.app/hc/reply-to
   deprecated: true
 - name: insert_article_in_reply
   display_name: Insert Article in Reply
@@ -149,7 +147,7 @@
   enabled: true
 - name: report_v4
   display_name: Report V4
-  enabled: true
+  enabled: false
   deprecated: true
 - name: contact_chatwoot_support_team
   display_name: Contact Chatwoot Support Team