Add QCDLoop Fortran

* Add QCDLoop v1.98 in Fortran.
   - c.f. https://qcdloop.fnal.gov/
* Permission to license QCDLoop as MIT (previously unlicensed) was given by
  author R. Keith Ellis via email on 2025-02-03.

recipes/qcdloop-fortran/license.patch

@@ -0,0 +1,40 @@
+From 4cf02f788bae19ecf4ab5a0a11a3b9cbe83d86b9 Mon Sep 17 00:00:00 2001
+From: Matthew Feickert <[email protected]>
+Date: Mon, 3 Feb 2025 13:05:17 -0700
+Subject: [PATCH] Add QCDLoop MIT license copyright R. Keith Ellis
+
+---
+ LICENSE | 21 +++++++++++++++++++++
+ 1 file changed, 21 insertions(+)
+ create mode 100644 LICENSE
+
+diff --git a/LICENSE b/LICENSE
+new file mode 100644
+index 0000000..bc2ad63
+--- /dev/null
++++ b/LICENSE
+@@ -0,0 +1,21 @@
++MIT License
++
++Copyright (c) 2007 R. Keith Ellis
++
++Permission is hereby granted, free of charge, to any person obtaining a copy
++of this software and associated documentation files (the "Software"), to deal
++in the Software without restriction, including without limitation the rights
++to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
++copies of the Software, and to permit persons to whom the Software is
++furnished to do so, subject to the following conditions:
++
++The above copyright notice and this permission notice shall be included in all
++copies or substantial portions of the Software.
++
++THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
++IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
++FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
++AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
++LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
++OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
++SOFTWARE.
+-- 
+2.47.1
+

recipes/qcdloop-fortran/meta.yaml

@@ -0,0 +1,75 @@
+{% set name = "qcdloop-fortran" %}
+{% set version = "1.98" %}
+
+package:
+  name: {{ name }}
+  version: {{ version }}
+
+source:
+    url: https://qcdloop.fnal.gov/QCDLoop-{{ version }}.tar.gz
+    sha256: 917ba1daa6d526937a93e0e0b3392103660efdeef2880a0d9188bdc0ad9c0035
+    # QCDLoop was unversioned but permission was given by Keith Ellis to license under MIT on 2025-02-03
+    patches:
+      - license.patch
+
+build:
+  number: 0
+
+outputs:
+  - name: {{ name }}-static
+
+    build:
+      skip: true  # [win]
+      script:
+        # Enable extended-source with '-ffixed-line-length-none' for long lines
+        # c.f. https://gcc.gnu.org/onlinedocs/gfortran/Fortran-Dialect-Options.html#index-ffixed-line-length-n
+        - cd ql
+        - make FC=$FC FFLAGS="$FFLAGS -std=legacy -Wall -ffixed-line-length-none"
+        - cd ..
+
+        # Install
+        - mv ql/libqcdloop.a $PREFIX/lib/
+
+        - mkdir -p $PREFIX/include/ql
+        - mv ql/*.mod $PREFIX/include/ql/
+
+    requirements:
+      build:
+        - {{ stdlib('c') }}
+        - {{ compiler('fortran') }}
+        - make
+        - libtool
+      run:
+        # QCDLoop calls FF functions
+        - ff-static
+
+    test:
+      source_files:
+        - test.f
+      requires:
+        - {{ compiler('fortran') }}
+      commands:
+        - test -f $PREFIX/lib/libqcdloop.a
+        - test -f $PREFIX/include/ql/qldiffi2.mod
+        - test -f $PREFIX/include/ql/solvequadratic.mod
+
+        - $FC test.f -o test $FFLAGS -I$PREFIX/include/ql -std=legacy $LDFLAGS -lqcdloop -lff
+        - ./test
+
+about:
+  home: https://qcdloop.fnal.gov/
+  summary: 'QCDLoop: one-loop scalar integrals'
+  description: |
+    QCDLoop is software for one-loop scalar Feynman integrals, evaluated
+    close to four dimensions. For integrals with all massive internal lines
+    the integrals are all known, both analytically and numerically.
+  license: MIT
+  license_family: MIT
+  license_file: LICENSE
+  dev_url: https://qcdloop.fnal.gov/
+  doc_url: https://qcdloop.fnal.gov/
+
+extra:
+  feedstock-name: qcdloop-fortran
+  recipe-maintainers:
+    - matthewfeickert