Fix corner cases for secondary key length checks in GSI

Some additional fixes needed on top of fixes for MB-22409:

1. MOI array index insert path should create NewSecondaryIndexEntry with isArray as false
2. Array secondary entry size check should be against maxArrayKeyBufferLength in index_entry L131
3. Add additional 2 bytes in buffer for optional count for duplicate array index
4. Scan co-ordinator secnBufPool should be increased with ENCODE_BUF_SAFE_PAD
5. Remove crashonerror / checkdbfatal errors for non-storage operations in slice writers.
6. Fix logging in array.go. Length should be logged not the key.
7. Remove duplicate logging in fdb/moi slice writers as it is already logged in array.go

These above three fixes will complete the fix for MB-22409. These fixes are more code change so were not done for the hotfix.