linkstatic = True is silently ignored under --dynamic_mode=fully

### Description of the bug

A per-target `linkstatic = True` on a `cc_binary` is silently ignored when the build is run with `--dynamic_mode=fully`. The target's `cc_library` deps are linked dynamically anyway, with no warning or error.

I'd expect a per-target attribute like `linkstatic` to override a command-line *default* rather than be overridden by it, and that is exactly the behavior under `--dynamic_mode=default`: there, `linkstatic = True` and `linkstatic = False` on otherwise identical binaries produce static and dynamic linkage respectively. Only under `fully` does the flag win over the explicit per-target request.

If overriding really is intended, it should at least not be silent, since it means `--dynamic_mode=fully` can change the linkage of targets that have deliberately opted out of it.

(`--dynamic_mode=off` has the mirror-image behavior: `linkstatic = False` is silently ignored. That direction is at least suggested by the flag name; `fully` overriding an explicit `True` is the surprising one.)

### Which category does this issue belong to?

C++ Rules

### What's the simplest, easiest way to reproduce this bug?

`MODULE.bazel`:

```python
module(name = "linkstatic_repro")
bazel_dep(name = "rules_cc", version = "0.2.17")
```

`lib.h`:
```c++
int f();
```

`lib.cc`:
```c++
#include "lib.h"
int f() { return 42; }
```

`main.cc`:
```c++
#include "lib.h"
int main() { return f() == 42 ? 0 : 1; }
```

`BUILD`:
```python
load("@rules_cc//cc:cc_binary.bzl", "cc_binary")
load("@rules_cc//cc:cc_library.bzl", "cc_library")

cc_library(name = "lib", srcs = ["lib.cc"], hdrs = ["lib.h"])

cc_binary(name = "static_bin", srcs = ["main.cc"], deps = [":lib"], linkstatic = True)
cc_binary(name = "dynamic_bin", srcs = ["main.cc"], deps = [":lib"], linkstatic = False)
```

Then check whether each binary ends up with a `NEEDED` entry for the dep's shared library:

```bash
for mode in default fully off; do
bazel build --dynamic_mode=$mode //:static_bin //:dynamic_bin >/dev/null 2>&1
echo "--dynamic_mode=$mode"
for t in static_bin dynamic_bin; do
readelf -d bazel-bin/$t | grep -q libliblib.so && r=dynamic || r=static
echo " $t -> $r"
done
done
```

### What operating system are you running Bazel on?

Ubuntu 24.04, Linux 6.8.0 x86_64, gcc 13.3.0

### What is the output of `bazel info release`?

`release 9.2.0`

### Have you found anything relevant by searching the web?

I didn't find an existing issue for this; #16479 and #21301 touch `linkstatic` but not its interaction with `--dynamic_mode`.

### Any other information, logs, or outputs that you want to share?

Output of the script above:

```
--dynamic_mode=default
static_bin (linkstatic=True ) -> static
dynamic_bin (linkstatic=False) -> dynamic
--dynamic_mode=fully
static_bin (linkstatic=True ) -> dynamic <-- linkstatic=True ignored
dynamic_bin (linkstatic=False) -> dynamic
--dynamic_mode=off
static_bin (linkstatic=True ) -> static
dynamic_bin (linkstatic=False) -> static <-- linkstatic=False ignored
```

The `fully` build produces no diagnostic mentioning `linkstatic`.

Start with the MODULE.bazel and BUILD reproduction, then run the provided loop with readelf for default, fully, and off. Trace how the cc_binary linkstatic attribute is combined with --dynamic_mode; done means the precedence is intentional and documented by behavior, with no silent mismatch for an explicit per-target setting.

Written by the indexing model from the issue text.