[EPIC] Optimize performance for slow expressions

### What is the problem the feature request solves?

The following expressions are slower with Comet enabled, according to the benchmarks in https://github.com/apache/datafusion-comet/pull/2984

This epic is for tracking progress on optimizing these. Separate issues should be created and linked to from this table. Some issues already exist (look for issues [tagged with the performance label](https://github.com/apache/datafusion-comet/issues?q=state%3Aopen%20label%3A%22performance%22)).

Also, I'd like to point out that this table was generated by AI and contains some duplicate entries, and may also have errors.

### Strings

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometStringExpressionBenchmark | octet_length | 373.0 | 0.4X | 60.0% |
| CometStringExpressionBenchmark | trim | 435.0 | 0.4X | 60.0% |
| CometStringExpressionBenchmark | ltrim | 434.0 | 0.4X | 60.0% |
| CometStringExpressionBenchmark | rtrim | 436.0 | 0.4X | 60.0% |
| CometStringExpressionBenchmark | repeat | 720.0 | 0.4X | 60.0% |
| CometStringExpressionBenchmark | concat | 595.0 | 0.5X | 50.0% |
| CometStringExpressionBenchmark | startswith | 396.0 | 0.5X | 50.0% |
| CometStringExpressionBenchmark | ascii | 405.0 | 0.6X | 40.0% |
| CometStringExpressionBenchmark | bit_length | 451.0 | 0.6X | 40.0% |
| CometStringExpressionBenchmark | concat_ws | 702.0 | 0.6X | 40.0% |
| CometStringExpressionBenchmark | instr | 3805.0 | 0.6X | 40.0% |
| CometStringExpressionBenchmark | endswith | 414.0 | 0.6X | 40.0% |
| CometStringExpressionBenchmark | chr | 27.0 | 0.8X | 20.0% |
| CometStringExpressionBenchmark | space | 28.0 | 0.8X | 20.0% |
| CometStringExpressionBenchmark | translate | 28908.0 | 0.8X | 20.0% |
| CometStringExpressionBenchmark | initCap | 4560.0 | 0.9X | 10.0% |
| CometStringExpressionBenchmark | rlike | 3396.0 | 0.9X | 10.0% |

### Date/Timestamp

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometDatetimeExpressionBenchmark | [Timestamp Truncate](https://github.com/apache/datafusion-comet/issues/2995) | 134.0 | 0.6X | 40.0% |
| CometDatetimeExpressionBenchmark | [Date Truncate](https://github.com/apache/datafusion-comet/issues/2998) | 34.0 | 0.8X | 20.0% |
| CometDatetimeExpressionBenchmark | Timestamp Extract - year | 61.0 | 0.8X | 20.0% |
| CometDatetimeExpressionBenchmark | Date Extract - year | 24.0 | 0.9X | 10.0% |
| CometDatetimeExpressionBenchmark | Date Arithmetic - date_add | 24.0 | 0.9X | 10.0% |

### Arrays

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometArrayExpressionBenchmark | array_remove | 12.0 | 0.5X | 50.0% |
| CometArrayExpressionBenchmark | array_compact | 13.0 | 0.5X | 50.0% |
| CometArrayExpressionBenchmark | array_max | 13.0 | 0.8X | 20.0% |
| CometArrayExpressionBenchmark | array_min | 12.0 | 0.8X | 20.0% |
| CometArrayExpressionBenchmark | array_contains | 15.0 | 0.9X | 10.0% |
| CometArrayExpressionBenchmark | array_distinct | 14.0 | 0.9X | 10.0% |
| CometArrayExpressionBenchmark | array_append | 12.0 | 0.9X | 10.0% |
| CometArrayExpressionBenchmark | arrays_overlap | 12.0 | 0.9X | 10.0% |
| CometArrayExpressionBenchmark | array_insert | 11.0 | 0.9X | 10.0% |
| CometArrayExpressionBenchmark | array_join | 13.0 | 0.9X | 10.0% |

### Hash

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometHashExpressionBenchmark | xxhash64_multi | 15.0 | 0.9X | 10.0% |
| CometHashExpressionBenchmark | murmur3_hash_single | 13.0 | 0.9X | 10.0% |
| CometHashExpressionBenchmark | murmur3_hash_multi | 14.0 | 0.9X | 10.0% |
| CometHashExpressionBenchmark | sha2_224 | 28.0 | 0.8X | 20.0% |
| CometHashExpressionBenchmark | sha2_256 | 29.0 | 0.8X | 20.0% |
| CometHashExpressionBenchmark | sha2_512 | 34.0 | 0.6X | 40.0% |
| CometHashExpressionBenchmark | sha2_384 | 34.0 | 0.7X | 30.0% |

### Bitwise

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometBitwiseExpressionBenchmark | shift_right_unsigned | 10.0 | 0.9X | 10.0% |
| CometBitwiseExpressionBenchmark | shift_left | 10.0 | 0.7X | 30.0% |
| CometBitwiseExpressionBenchmark | bitwise_or | 12.0 | 0.8X | 20.0% |
| CometBitwiseExpressionBenchmark | bitwise_xor | 11.0 | 0.8X | 20.0% |
| CometBitwiseExpressionBenchmark | bitwise_not | 10.0 | 0.8X | 20.0% |
| CometBitwiseExpressionBenchmark | shift_right | 10.0 | 0.8X | 20.0% |
| CometBitwiseExpressionBenchmark | bit_count | 10.0 | 0.8X | 20.0% |

### Cast

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometCastStringToNumericBenchmark | CAST String to BYTE | 59.0 | 0.8X | 20.0% |
| CometCastStringToNumericBenchmark | CAST String to SHORT | 59.0 | 0.8X | 20.0% |
| CometCastStringToNumericBenchmark | CAST String to INT | 56.0 | 0.8X | 20.0% |
| CometCastStringToNumericBenchmark | CAST String to LONG | 59.0 | 0.8X | 20.0% |

### Comparison

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometComparisonExpressionBenchmark | greater_than | 11.0 | 0.8X | 20.0% |
| CometComparisonExpressionBenchmark | is_null | 10.0 | 0.8X | 20.0% |
| CometComparisonExpressionBenchmark | is_nan_float | 10.0 | 0.8X | 20.0% |
| CometComparisonExpressionBenchmark | not_equal_to | 13.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | less_than | 12.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | less_than_or_equal | 11.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | greater_than_or_equal | 11.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | equal_null_safe | 10.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | is_not_null | 10.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | and | 11.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | or | 11.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | not | 10.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | in_list | 10.0 | 0.9X | 10.0% |
| CometComparisonExpressionBenchmark | not_in_list | 11.0 | 0.9X | 10.0% |

### Math

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometMathExpressionBenchmark | hex_int | 11.0 | 0.7X | 30.0% |
| CometMathExpressionBenchmark | floor | 10.0 | 0.8X | 20.0% |
| CometMathExpressionBenchmark | hex_long | 11.0 | 0.8X | 20.0% |
| CometMathExpressionBenchmark | unhex | 13.0 | 0.8X | 20.0% |
| CometMathExpressionBenchmark | unary_minus | 10.0 | 0.8X | 20.0% |
| CometMathExpressionBenchmark | ceil | 11.0 | 0.9X | 10.0% |
| CometMathExpressionBenchmark | round | 19.0 | 0.9X | 10.0% |
| CometMathExpressionBenchmark | atan2 | 11.0 | 0.9X | 10.0% |
| CometMathExpressionBenchmark | log | 11.0 | 0.9X | 10.0% |
| CometMathExpressionBenchmark | log10 | 11.0 | 0.9X | 10.0% |

### Others

| Benchmark File | Expression | Spark Time (ms) | Comet Relative | Slowdown |
|----------------|------------|-----------------|----------------|----------|
| CometConditionalExpressionBenchmark | Case When Expr | 41.0 | 0.8X | 20.0% |
| CometPredicateExpressionBenchmark | in Expr | 42.0 | 0.8X | 20.0% |
| CometConditionalExpressionBenchmark | If Expr | 38.0 | 0.9X | 10.0% |

### Describe the potential solution

_No response_

### Additional context

_No response_