Cannot open source members with '£' in name (listed correctly but not found on open)

Hi,

I'm having trouble opening source members whose names contain the special character `£`. They are correctly listed in the Member Browser (the name is displayed properly), but when I try to open them, the extension reports that the object cannot be found. Interestingly, this only happens with `£`: other variant characters like `$` work without any issue.

The following error is what I see:

```
The editor could not be opened because the file was not found.
```

## To Reproduce

1. Open the Member Browser
2. Locate a source member whose name contains `£`
3. Click to open it
4. Observe the error

---

This issue seems related to previous ones:

* #198 — issue with `£` due to CCSID/PASE mismatch
* #701 — regression introduced in v1.3.4 (later fixed)
* #719 — similar issue with `§`, fixed by extending the valid character regexp

### Observations

* Member names are displayed correctly in the browser
* The problem only occurs when opening the member
* This suggests a mismatch between:

* how names are retrieved (works correctly)
* how they are later resolved/opened (fails)

From #198:

* `£` in CCSID 280 may map to `#` in other CCSIDs (e.g. 37 or PASE environments)

From #701 / #719:

* Issues were also caused by regexp validation of allowed characters

### Here's what I thought:

It looks like there might still be some inconsistency between:

* encoding handling (CCSID / PASE)
* and/or character validation / path resolution

So even though the UI shows the correct name, the underlying path used to open the member may not match the actual object.

## I tried the following workarounds:

* Changing `sourceFileCCSID`
* Checking PASE configuration
* Comparing behavior with `$` (works) vs `£` (fails)
* Switching from/to pre-release version

None of these resolved the issue in this environment.

---

I'm still relatively new to the IBM i / AS400 world, so I might be missing something obvious — please let me know if you need more details or if I can run additional tests.

Thanks for your help!

---

| Context | Version |
| -------------------------- | --------- |
| Code for IBM i version | 2.18.3 |
| Visual Studio Code version | 1.117.0 |
| Operating System | win32_x64 |

Active extensions

```
Auto Rename Tag (auto-rename-tag): 0.1.10
Background (code-background): 4.0.4
CL (vscode-clle): 1.2.4
COBOL (cobol): 26.4.3
CSS Language Features (css-language-features): 10.0.0
Code for IBM i Walkthroughs (vscode-ibmi-walkthroughs): 0.5.0
Configuration Editing (configuration-editing): 10.0.0
DSPF Designer (dspf-designer): 2.1.1
Db2 for IBM i (vscode-db2i): 1.17.0
ESLint (vscode-eslint): 3.0.24
Emmet (emmet): 10.0.0
Error Lens (errorlens): 3.28.0
Extension Authoring (extension-editing): 10.0.0
Git (git): 10.0.0
Git Base (git-base): 10.0.0
GitHub (github): 0.0.1
GitHub Authentication (github-authentication): 0.0.2
GitHub Copilot Chat (copilot-chat): 0.45.1
HTML Language Features (html-language-features): 10.0.0
Highlight (vscode-highlight): 2.1.0
Highlight Matching Tag (highlight-matching-tag): 0.11.0
IBM i Debug (ibmidebug): 3.0.3
IBM i Project Explorer (vscode-ibmi-projectexplorer): 2.12.3
JSON Language Features (json-language-features): 10.0.0
JavaScript and TypeScript Language Features (typescript-language-features): 10.0.0
Live Server (LiveServer): 5.7.10
Markdown Language Features (markdown-language-features): 10.0.0
Merge Conflict (merge-conflict): 10.0.0
Microsoft Account (microsoft-authentication): 0.0.1
NPM support for VS Code (npm): 1.0.1
Node Debug Auto-attach (debug-auto-launch): 10.0.0
Pylance (vscode-pylance): 2026.2.100
Python (python): 2026.4.0
Python Debugger (debugpy): 2025.18.0
Python Environments (vscode-python-envs): 1.28.0
Python Indent (vsc-python-indent): 1.21.0
Server Ready Action (debug-server-ready): 10.0.0
Simple Browser (simple-browser): 10.0.0
Source Orbit (vscode-sourceorbit): 1.4.1
Terminal Suggest for VS Code (terminal-suggest): 1.0.1
code canvas app (code-canvas-app): 0.14.8
multi-command (multi-command): 1.6.0
npm Intellisense (npm-intellisense): 1.4.5
readme-preview (readme-preview): 0.0.3
vscode-icons (vscode-icons): 12.18.0
```

---

Remote system

|Setting|Value|
|-|-|
|IBM i OS|V7R4M0|
|Tech Refresh|12|
|CCSID Origin|65535|
|Runtime CCSID|1144|
|SQL runner|Yes|
|SQL|Enabled
|Source dates|Enabled

### Enabled features

|/usr/bin|/QOpenSys/pkgs/bin|/QSYS.lib/ILEDITOR.lib|/QIBM/ProdData/IBMiDebugService/bin|/QOpenSys/QIBM/ProdData/JavaVM/jdk80|
|-|-|-|-|-|
|attr|bash|GETNEWLIBL.PGM|startDebugService.sh|64bit|
|iconv|chsh||||
|setccsid|ls||||
|tar|md5sum||||
|uname|sort||||
||stat||||

Shell env

```bash
BUILDLIB=W_GD1
CURLIB=W_GD1
HOME=/home/EURGD1
HOST=172.20.10.100
LIBLS=W_GD1 QGPL QRPG SMESTD SMEUP_OBJ SMEDEV SME_EUR EUR_TEMP SME_TST SMEDATTST QTEMP
LOGIN=eurgd1
LOGNAME=eurgd1
MAIL=/var/spool/mail/eurgd1
PATH=/QOpenSys/usr/bin:/usr/ccs/bin:/QOpenSys/usr/bin/X11:/usr/sbin:.:/usr/bin
SHELL=/QOpenSys/usr/bin/bsh
SSH_CLIENT=10.38.202.208 54054 22
SSH_CONNECTION=10.38.202.208 54054 172.20.10.100 22
TZ=-1,M3.5.0,M10.5.0/03:00:00
USER=eurgd1
USERNAME=eurgd1
WORKDIR=/home/EURGD1
```

Variants

```json
{
"american": "#@$",
"local": "£§$"
}
```