feat: refactor four attention converters with TRT add_attention_v2()

[zewenli98]

Description

This PR refactors four attention converters with TRT add_attention_v2(). Additionally, since newer torch rejects passing both is_causal=True and explicit attn_mask to SDPA, which aligns with TRT, some scenarios are gated in validators and the unreachable branches are pruned.

Fixes # (issue)

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified

[github-actions]

There are some changes that do not conform to Python style guidelines:

--- /home/runner/work/TensorRT/TensorRT/py/torch_tensorrt/dynamo/lowering/passes/eliminate_sym_min_int64_max.py	2026-07-17 18:09:43.975250+00:00
+++ /home/runner/work/TensorRT/TensorRT/py/torch_tensorrt/dynamo/lowering/passes/eliminate_sym_min_int64_max.py	2026-07-17 18:10:04.835218+00:00
@@ -2,11 +2,10 @@

import torch
from torch.fx import GraphModule, Node

from .pass_utils import clean_up_graph_after_modifications
-

_INT64_MAX = 2**63 - 1
_SYM_MIN = getattr(torch, "sym_min", None)

[github-actions]

There are some changes that do not conform to Python style guidelines:

--- /home/runner/work/TensorRT/TensorRT/py/torch_tensorrt/dynamo/lowering/passes/eliminate_sym_min_int64_max.py	2026-07-17 18:09:44.412631+00:00
+++ /home/runner/work/TensorRT/TensorRT/py/torch_tensorrt/dynamo/lowering/passes/eliminate_sym_min_int64_max.py	2026-07-17 18:10:05.940612+00:00
@@ -2,11 +2,10 @@

import torch
from torch.fx import GraphModule, Node

from .pass_utils import clean_up_graph_after_modifications
-

_INT64_MAX = 2**63 - 1
_SYM_MIN = getattr(torch, "sym_min", None)