redis: Add authentication support v4

[AmazingPP]

Replaces: #13951

Changes since v3:

• Fixed memory leak occurring after authentication failure.
• Added ECHO command in SCConfLogReopenSyncRedis to verify the connection is ready before writing logs, preventing spam in sync mode.

Changes since v2:

• Made authentication failure retry interval consistent with connection failure.

Changes since v1:

• Reworked async mode to use a state machine for connection and authentication.
• Authentication is now retried on failure.
• Handled reply == NULL in the authentication callback.
• Added a guard: if a Redis username is set without a password, ignore the username and log a warning.

Manual testing

I manually tested the changes in both sync and async modes across different scenarios. All expected results matched actual results.

Case	Scenario	Result
1	No auth	Success, logs written
2	Wrong password	Connection failed, error logged
3	Correct password	Success, logs written
4	Missing password	Connection failed, error logged
5	ACL (valid)	Success, logs written
6	ACL (wrong password)	Connection failed, error logged
7	ACL (no username provided)	Connection failed, error logged
8	Re-authentication	Connection recovered, logs written after re-auth

Contribution style:

• I have read the contributing guide lines at
  https://docs.suricata.io/en/latest/devguide/contributing/contribution-process.html

Our Contribution agreements:

• I have signed the Open Information Security Foundation contribution agreement at
  https://suricata.io/about/contribution-agreement/ (note: this is only required once)

Changes (if applicable):

• I have updated the User Guide (in doc/userguide/) to reflect the changes made
• I have updated the JSON schema (in etc/schema.json) to reflect all logging changes
  (including schema descriptions)
• I have created a ticket at
  https://redmine.openinfosecfoundation.org/projects/suricata/issues

Link to ticket: https://redmine.openinfosecfoundation.org/issues/7062

Describe changes:

• Add authentication support to the Redis logging output.
• Authentication configuration defaults to null for backward compatibility.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.87%. Comparing base (7ca95ee) to head (8bbe5bb).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #14002    +/-   ##
========================================
  Coverage   83.86%   83.87%            
========================================
  Files        1011     1011            
  Lines      275556   275671   +115     
========================================
+ Hits       231107   231207   +100     
- Misses      44449    44464    +15     

Flag	Coverage Δ
fuzzcorpus	63.51% <ø> (-0.01%)	⬇️
livemode	19.34% <ø> (-0.07%)	⬇️
pcap	44.75% <ø> (+<0.01%)	⬆️
suricata-verify	65.15% <ø> (+0.02%)	⬆️
unittests	59.14% <ø> (-0.03%)	⬇️

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